CSX (CSX) 10-K12 Feb 202019 FY Annual reportFinancial data

Company Profile

Cover Page

Cover Page - USD ($) $ in Billions	12 Months Ended
Cover Page - USD ($) $ in Billions	Dec. 31, 2019	Jan. 31, 2020	Jun. 30, 2019
Cover page.
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2019
Document Transition Report	false
Entity File Number	1-8022
Entity Registrant Name	CSX CORPORATION
Entity Incorporation, State or Country Code	VA
Entity Tax Identification Number	62-1051971
Entity Address, Address Line One	500 Water Street
Entity Address, Address Line Two	15th Floor
Entity Address, City or Town	Jacksonville
Entity Address, State or Province	FL
Entity Address, Postal Zip Code	32202
City Area Code	904
Local Phone Number	359-3200
Title of 12(b) Security	Common Stock, $1 Par Value
Trading Symbol	CSX
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 59
Entity Common Stock, Shares Outstanding		773,825,565
Entity Central Index Key	0000277948
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Amendment Flag	false

CONSOLIDATED INCOME STATEMENTS

CONSOLIDATED INCOME STATEMENTS - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
Revenue	$ 11,937	$ 12,250	$ 11,408
Expense
Labor and Fringe	2,616	2,738	2,946
Materials, Supplies and Other	1,784	1,967	2,113
Depreciation	1,349	1,331	1,315
Fuel	906	1,046	864
Equipment and Other Rents	408	395	429
Restructuring Charge (Note 1)	0	0	240
Equity Earnings of Affiliates	(91)	(96)	(219)
Total Expense	6,972	7,381	7,688
Operating Income	4,965	4,869	3,720
Interest Expense	(737)	(639)	(546)
Restructuring Charge - Non-Operating (Note 1)	0	0	(85)
Other Income - Net (Note 14)	88	74	53
Earnings Before Income Taxes	4,316	4,304	3,142
Income Tax (Expense) Benefit (Note 12)	(985)	(995)	2,329
Net Earnings	$ 3,331	$ 3,309	$ 5,471
Net Earnings Per Share
Basic (in dollars per share)	$ 4.18	$ 3.86	$ 6.01
Assuming Dilution (in dollars per share)	$ 4.17	$ 3.84	$ 5.99
Average Common Shares Outstanding (Millions)
Basic (shares)	796	857	911
Assuming Dilution (shares)	798	861	914

CONSOLIDATED COMPREHENSIVE INCO

CONSOLIDATED COMPREHENSIVE INCOME STATEMENTS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Net Earnings	$ 3,331	$ 3,309	$ 5,471
Other Comprehensive (Loss) Income - Net of Tax:
Total Other Comprehensive (Loss) Income	(14)	(175)	154
Total Comprehensive Earnings	3,317	3,134	5,625
Pension and Other Post-Employment Benefits
Other Comprehensive (Loss) Income - Net of Tax:
Total Other Comprehensive (Loss) Income	(15)	(164)	140
Other
Other Comprehensive (Loss) Income - Net of Tax:
Total Other Comprehensive (Loss) Income	$ 1	$ (11)	$ 14

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 30, 2016
Current Assets:
Cash and Cash Equivalents (Note 1)	$ 958	$ 858	$ 401	$ 603
Short-term Investments	996	253
Accounts Receivable - Net (Note 1)	986	1,010
Materials and Supplies	261	263
Other Current Assets	77	181
Total Current Assets	3,278	2,565
Properties	45,100	44,805
Accumulated Depreciation	(12,932)	(12,807)
Properties - Net (Note 6)	32,168	31,998
Right of Use Lease Asset (Note 7)	532	0
Other Long-term Assets	400	387
Total Assets	38,257	36,729
Current Liabilities:
Accounts Payable	1,043	949
Labor and Fringe Benefits Payable	489	550
Casualty, Environmental and Other Reserves	100	113
Current Maturities of Long-term Debt	245	18
Income and Other Taxes Payable	69	106
Other Current Liabilities	205	179
Total Current Liabilities	2,151	1,915
Casualty, Environmental and Other Reserves	205	211
Long-term Debt (Note 9)	15,993	14,739
Deferred Income Taxes - Net (Note 12)	6,961	6,690
Long-term Lease Liability (Note 7)	493	0
Other Long-term Liabilities	591	594
Total Liabilities	26,394	24,149
Shareholders' Equity:
Common Stock, $1 Par Value (Note 3)	773	818
Other Capital	346	249
Retained Earnings (Note 1)	11,404	12,157
Accumulated Other Comprehensive Loss (Note 16)	(675)	(661)
Noncontrolling Minority Interest	15	17
Total Shareholders' Equity	11,863	12,580	$ 14,721	$ 11,694
Total Liabilities and Shareholders' Equity	38,257	36,729
Investments in Conrail
Current Assets:
Investment in Affiliates and Other Companies		943
Affiliates and Other Companies
Current Assets:
Investment in Affiliates and Other Companies	$ 897	$ 836

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Common stock par value (in dollars per share)	$ 1	$ 1

CONSOLIDATED CASH FLOW STATEMEN

CONSOLIDATED CASH FLOW STATEMENTS - USD ($) $ in Millions	12 Months Ended
CONSOLIDATED CASH FLOW STATEMENTS - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
OPERATING ACTIVITIES
Net Earnings	$ 3,331	$ 3,309	$ 5,471
Adjustments to Reconcile Net Earnings to Net Cash
Depreciation	1,349	1,331	1,315
Restructuring Charge (Note 1)	0	0	325
Cash Payments for Restructuring Charge	0	(15)	(187)
Deferred Income Taxes	273	279	(3,233)
Earnings of Equity-method Investments	(91)	(96)	(219)
Gain on Property Dispositions	(151)	(154)	(18)
Other Operating Activities	22	(21)	(17)
Changes in Operating Assets and Liabilities:
Accounts Receivable	45	(46)	(70)
Other Current Assets	68	101	1
Accounts Payable	98	104	41
Income and Other Taxes Payable	2	(104)	20
Other Current Liabilities	(96)	(47)	43
Net Cash Provided by Operating Activities	4,850	4,641	3,472
INVESTING ACTIVITIES
Property Additions	(1,657)	(1,745)	(2,040)
Purchase of Short-term Investments	(2,838)	(736)	(782)
Proceeds from Sales of Short-term Investments	2,108	505	1,193
Proceeds from Property Dispositions	254	319	97
Other Investing Activities	31	(27)	37
Net Cash Used in Investing Activities	(2,102)	(1,684)	(1,495)
FINANCING ACTIVITIES
Long-term Debt Issued (Note 10)	2,000	3,000	850
Long-term Debt Repaid (Note 10)	(518)	(19)	(333)
Dividends Paid	(763)	(751)	(708)
Shares Repurchased	(3,373)	(4,671)	(1,970)
Other Financing Activities	6	(59)	(18)
Net Cash Used in Financing Activities	(2,648)	(2,500)	(2,179)
Net Increase (Decrease) in Cash and Cash Equivalents	100	457	(202)
CASH AND CASH EQUIVALENTS
Cash and Cash Equivalents at Beginning of Period	858	401	603
Cash and Cash Equivalents at End of Period	958	858	401
SUPPLEMENTAL CASH FLOW INFORMATION
Interest Paid - Net of Amounts Capitalized	717	614	555
Income Taxes Paid	$ 691	$ 814	$ 911

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Millions	Total	Common Shares Outstanding	Common Stock and Other Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)		Non- controlling Minority Interest
Common Shares Outstanding, beginning balance (in shares) at Dec. 30, 2016		928,180
Shareholders' Equity, beginning balance at Dec. 30, 2016	$ 11,694		$ 1,066	$ 11,253	$ (640)	[1]	$ 15
Comprehensive Earnings:
Net Earnings	5,471			5,471
Total Other Comprehensive (Loss) Income	154				154	[1]
Total Comprehensive Earnings	5,625
Common stock dividends, per share	$ (708)			(708)
Share Repurchases (in shares)	(39,000)	(38,785)
Share Repurchases	$ (1,970)		(39)	(1,931)
Other (in shares)		456
Other	80		80	(1)			1
Common Shares Outstanding, ending balance (in shares) at Dec. 31, 2017		889,851
Shareholders' Equity, ending balance at Dec. 31, 2017	14,721		1,107	14,084	(486)	[1]	16
Comprehensive Earnings:
Accumulated other comprehensive loss, tax					162
Net Earnings	3,309			3,309
Total Other Comprehensive (Loss) Income	(175)				(175)	[1]
Total Comprehensive Earnings	3,134
Common stock dividends, per share	$ (751)			(751)
Share Repurchases (in shares)	(72,000)	(72,264)
Share Repurchases	$ (4,671)		(72)	(4,599)
Other (in shares)		593
Other	147		32	114			1
Common Shares Outstanding, ending balance (in shares) at Dec. 31, 2018		818,180
Shareholders' Equity, ending balance at Dec. 31, 2018	12,580		1,067	12,157	(661)	[1]	17
Comprehensive Earnings:
Accumulated other comprehensive loss, tax					180
Net Earnings	3,331			3,331
Total Other Comprehensive (Loss) Income	(14)				(14)	[1]
Total Comprehensive Earnings	3,317
Common stock dividends, per share	$ (763)			(763)
Share Repurchases (in shares)	(48,000)	(47,819)
Share Repurchases	$ (3,373)		(48)	(3,325)
Other (in shares)		3,110
Other	102		100	4			(2)
Common Shares Outstanding, ending balance (in shares) at Dec. 31, 2019		773,471
Shareholders' Equity, ending balance at Dec. 31, 2019	$ 11,863		$ 1,119	$ 11,404	(675)	[1]	$ 15
Comprehensive Earnings:
Accumulated other comprehensive loss, tax					$ 184

[1]	Accumulated Other Comprehensive Loss year-end balances shown above are net of tax. The associated taxes were $184 million , $180 million and $162 million for 2019 , 2018 and 2017 , respectively. For additional information see Note 16, Other Comprehensive Income.

CONSOLIDATED STATEMENTS OF CH_2

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Stockholders' Equity [Abstract]
Common stock dividends, per share (in dollars per share)	$ 0.96	$ 0.88	$ 0.78

Nature of Operations and Signif

Nature of Operations and Significant Accounting Policies	12 Months Ended
Nature of Operations and Significant Accounting Policies	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Operations and Significant Accounting Policies	Nature of Operations and Significant Accounting Policies Business CSX Corporation together with its subsidiaries ("CSX" or the “Company”), based in Jacksonville, Florida, is one of the nation's leading transportation companies. The Company provides rail-based transportation services including traditional rail service, the transport of intermodal containers and trailers, as well as other transportation services such as rail-to-truck transfers and bulk commodity operations. CSX Transportation, Inc. CSX’s principal operating subsidiary, CSX Transportation, Inc. (“CSXT”), provides an important link to the transportation supply chain through its approximately 20,000 route mile rail network, which serves major population centers in 23 states east of the Mississippi River, the District of Columbia and the Canadian provinces of Ontario and Quebec. It has access to over 70 ocean, river and lake port terminals along the Atlantic and Gulf Coasts, the Mississippi River, the Great Lakes and the St. Lawrence Seaway. The Company’s intermodal business links customers to railroads via trucks and terminals. CSXT also serves thousands of production and distribution facilities through track connections to more than 230 short-line and regional railroads. CSXT is also responsible for the Company's real estate sales, leasing, acquisition and management and development activities. Substantially all of these activities are focused on supporting railroad operations. Other Entities In addition to CSXT, the Company’s subsidiaries include CSX Intermodal Terminals, Inc. (“CSX Intermodal Terminals”), Total Distribution Services, Inc. (“TDSI”), Transflo Terminal Services, Inc. (“Transflo”), CSX Technology, Inc. (“CSX Technology”) and other subsidiaries. CSX Intermodal Terminals owns and operates a system of intermodal terminals, predominantly in the eastern United States and also performs drayage services (the pickup and delivery of intermodal shipments) for certain customers and trucking dispatch operations. TDSI serves the automotive industry with distribution centers and storage locations. Transflo connects non-rail served customers to the many benefits of rail by transferring products from rail to trucks. The biggest Transflo markets are chemicals and agriculture, which includes shipments of plastics and ethanol. CSX Technology and other subsidiaries provide support services for the Company. NOTE 1. Nature of Operations and Significant Accounting Policies, continued Lines of Business During 2019 , the Company's services generated $11.9 billion of revenue and served three primary lines of business: merchandise, coal and intermodal. • The merchandise business shipped 2.7 million carloads ( 43 percent of volume) and generated 64 percent of revenue in 2019 . The Company’s merchandise business is comprised of shipments in the following diverse markets: chemicals, automotive, agricultural and food products, minerals, fertilizers, forest products, and metals and equipment. • The coal business shipped 843 thousand carloads ( 14 percent of volume) and generated 17 percent of revenue in 2019 . The Company transports domestic coal, coke and iron ore to electricity-generating power plants, steel manufacturers and industrial plants as well as export coal to deep-water port facilities. Roughly one-third of export coal and the majority of the domestic coal that the Company transports is used for generating electricity. • The intermodal business shipped 2.7 million units ( 43 percent of volume) and generated 15 percent of revenue in 2019 . The intermodal business combines the superior economics of rail transportation with the flexibility of trucks and offers a cost and environmental advantage over long-haul trucking. Through a network of approximately 30 terminals, the intermodal business serves all major markets east of the Mississippi River and transports mainly manufactured consumer goods in containers, providing customers with truck-like service for longer shipments. Other revenue accounted for 4 percent of the Company’s total revenue in 2019 . This revenue category includes revenue from regional subsidiary railroads, demurrage, storage at intermodal facilities, revenue for customer volume commitments not met, switching, other incidental charges and adjustments to revenue reserves. Revenue from regional railroads includes shipments by railroads that the Company does not directly operate. Demurrage represents charges assessed when freight cars or other equipment are held beyond a specified period of time. Switching represents charges assessed when a railroad switches cars for a customer or another railroad. Employees The Company's number of employees was nearly 21,000 as of December 2019 , which includes approximately 17,000 union employees. Most of the Company’s employees provide or support transportation services. Basis of Presentation In the opinion of management, the accompanying consolidated financial statements contain all normal, recurring adjustments necessary to fairly present the financial position of CSX and its subsidiaries at December 31, 2019 and December 31, 2018 , and the consolidated statements of income, comprehensive income, cash flows and changes in shareholders’ equity for fiscal years 2019 , 2018 and 2017 . Where applicable, prior year information has been reclassified to conform to current presentation. In addition, management has evaluated and disclosed all material events occurring subsequent to the date of the financial statements up to the date this annual report is filed on Form 10-K. NOTE 1. Nature of Operations and Significant Accounting Policies, continued Fiscal Year Through the second quarter 2017, CSX followed a 52/53 week fiscal reporting calendar with the last day of each reporting period ending on a Friday. On July 7, 2017, the Board of Directors of CSX approved a change in the fiscal reporting calendar from a 52/53 week year ending on the last Friday of December to a calendar year ending on December 31 each year, effective beginning with fiscal third quarter 2017. Related to the change in the fiscal calendar, 2019 and 2018 both contained 365 days while 2017 contained 366 days. This change did not materially impact comparability of the Company’s financial results for fiscal year 2017. Accordingly, the change to a calendar fiscal year was made on a prospective basis and operating results for prior periods were not adjusted. The Company was not required to file a transition report because this change was not deemed a change in fiscal year for purposes of reporting subject to Rule 13a-10 or Rule 15d-10 of the Securities Exchange Act of 1934 as the new fiscal year commenced with the end of the prior fiscal year end. Except as otherwise specified, references to full years indicate CSX’s fiscal years ended on December 31, 2019, December 31, 2018 and December 31, 2017. Principles of Consolidation The consolidated financial statements include results of operations of CSX and subsidiaries over which CSX has majority ownership or financial control. All significant intercompany accounts and transactions have been eliminated. Most investments in companies that were not majority-owned were carried at cost (if less than 20% owned and the Company has no significant influence) or were accounted for under the equity method (if the Company has significant influence but does not have control). These investments are reported within Investment in Conrail or Affiliates and Other Companies on the consolidated balance sheets. Cash and Cash Equivalents On a daily basis, cash in excess of current operating requirements is invested in various highly liquid investments having a typical maturity date of three months or less at the date of acquisition. These investments are carried at cost, which approximated market value, and are classified as cash equivalents. Investments Investments in instruments with original maturities greater than three months that will mature in less than one year are classified as short-term investments. Investments with original maturities of one year or greater are initially classified within other long-term assets, and the classification is re-evaluated at each balance sheet date. Materials and Supplies Materials and supplies in the consolidated balance sheets are carried at average costs and consist primarily of parts used in the repair and maintenance of track structure, equipment, and CSXT’s freight car and locomotive fleets, as well as fuel. NOTE 1. Nature of Operations and Significant Accounting Policies, continued New Accounting Pronouncements In February 2016, the FASB issued ASU, Leases , which requires lessees to recognize most leases on their balance sheets as a right-of-use asset with a corresponding lease liability. Lessor accounting under the standard is substantially unchanged. Additional qualitative and quantitative disclosures are also required. CSX adopted the standard effective January 1, 2019 using the cumulative-effect adjustment transition method, which applies the provisions of the standard at the effective date without adjusting the comparative periods presented. The Company adopted the following practical expedients and elected the following accounting policies related to this standard update: • Carry forward of historical lease classifications and current accounting treatment for existing land easements; • Short-term lease accounting policy election allowing lessees to not recognize right-of-use assets and liabilities for leases with a term of 12 months or less; and • The option to not separate lease and non-lease components for certain equipment lease asset categories such as freight car, vehicles and work equipment. Adoption of this standard resulted in the recognition of operating lease right-of-use assets and corresponding lease liabilities of $534 million on the consolidated balance sheet as of January 1, 2019 . This amount is lower than previous estimates due to a lease amendment. The Company’s accounting for finance leases remained substantially unchanged . The standard did not materially impact operating results or liquidity. Disclosures related to the amount, timing and uncertainty of cash flows arising from leases are included in Note 7, Leases . In June 2016, the FASB issued ASU Measurement of Credit Losses on Financial Instruments , which replaces current methods for evaluating impairment of financial instruments not measured at fair value, including trade accounts receivable and certain debt securities, with a current expected credit loss model. CSX adopted this new standard update effective January 1, 2020. Adoption will not have a material effect on the Company's results of operations. Use of Estimates The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires that management make estimates in reporting the amounts of certain assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amount of certain revenues and expenses during the reporting period. Actual results may differ from those estimates. Critical accounting estimates using management judgment are made for the following areas: • personal injury, environmental and legal reserves (see Note 5, Casualty, Environmental and Other Reserves ); • pension and post-retirement medical plan accounting (see Note 9, Employee Benefit Plans ); and • depreciation policies for assets under the group-life method (see Note 6, Properties ). NOTE 1. Nature of Operations and Significant Accounting Policies, continued Restructuring Charge Through an involuntary separation program with enhanced benefits to further its strategic objectives, CSX reduced its management workforce by approximately 950 employees during 2017. The Company was focused on driving efficiencies through process improvement and responding to business mix shifts. These management reductions were designed to further streamline general and administrative and operating support functions to speed decision making and further control costs. The involuntary separation program was essentially completed in April 2017. The restructuring charge in 2017 includes costs related to the management workforce reduction program, executive retirements, reimbursement arrangements with MR Argent Advisor LLC (“Mantle Ridge”) and the Company’s former President and Chief Executive Officer, E. Hunter Harrison, the proration of equity awards and other advisory costs related to the leadership transition. Payments related to the 2017 restructuring charge were substantially complete as of March 31, 2018. Expenses related to the management workforce reduction and other restructuring costs totaled $325 million in 2017 and are shown in the following table. Fiscal Year 2017 (Dollars in millions) Operating Restructuring Charge Non-Operating Restructuring Charge Severance and Pension $ 98 $ 56 Other Post-Retirement Benefits Curtailment — 17 Employee Equity Awards Proration and Other 23 — Subtotal Management Workforce Reduction $ 121 $ 73 Reimbursement Arrangements 84 — Executive Equity Awards Proration 24 — Pension Settlement Charge — 12 Advisory Fees Related to Shareholder Matters 11 — Total Restructuring Charge $ 240 $ 85

Earnings Per Share

Earnings Per Share	12 Months Ended
Earnings Per Share	Dec. 31, 2019
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share The following table sets forth the computation of basic earnings per share and earnings per share, assuming dilution: Fiscal Years 2019 2018 2017 Numerator (Dollars in Millions) : Net Earnings $ 3,331 $ 3,309 $ 5,471 Dividend Equivalents on Restricted Stock — (1 ) (1 ) Net Earnings, Attributable to Common Shareholders $ 3,331 $ 3,308 $ 5,470 Denominator (Units in Millions) : Average Common Shares Outstanding 796 857 911 Other Potentially Dilutive Common Shares 2 4 3 Average Common Shares Outstanding, Assuming Dilution 798 861 914 Net Earnings Per Share, Basic $ 4.18 $ 3.86 $ 6.01 Net Earnings Per Share, Assuming Dilution $ 4.17 $ 3.84 $ 5.99 Basic earnings per share is based on the weighted-average number of shares of common stock outstanding. Earnings per share, assuming dilution, is based on the weighted-average number of shares of common stock outstanding and common stock equivalents adjusted for the effects of common stock that may be issued as a result of potentially dilutive instruments. CSX's potentially dilutive instruments are made up of equity awards including performance units and employee stock options. When calculating diluted earnings per share, the potential shares that would be outstanding if all outstanding stock options were exercised are included. This number is different from outstanding stock options, which is included in Note 4, Stock Plans and Share-Based Compensation , because it is offset by shares CSX could repurchase using the proceeds from these hypothetical exercises to obtain the common stock equivalent. Approximately 877 thousand , 479 thousand and 7.6 million of total average outstanding stock options for 2019, 2018 and 2017, respectively, were excluded from the diluted earnings per share calculation because their effect was antidilutive. Share Repurchase Programs In January 2019, the Company announced a $5 billion share repurchase program ("January 2019 program"). At December 31, 2019, approximately $1.8 billion of authority remains under this program. Previously, share repurchases were completed under the following: • A share repurchase program originally announced in October 2017 for $1.5 billion , and later increased to $5 billion in February 2018, that was completed in January 2019 ("October 2017 program"). • A share repurchase program originally announced in April 2017 for $1 billion , and later increased to $1.5 billion in July 2017, that was completed in October 2017. • A $2 billion share repurchase program announced in April 2015 that was completed in April 2017. NOTE 2. Earnings Per Share, continued Share repurchases may be made through a variety of methods including, but not limited to, open market purchases, purchases pursuant to Rule 10b5-1 plans, accelerated share repurchases and negotiated block purchases. The timing of share repurchases depends upon management's assessment of marketplace conditions and other factors, and the program remains subject to the discretion of the Board of Directors. Future share repurchases are expected to be funded by cash on hand, cash generated from operations and debt issuances. Shares are retired immediately upon repurchase. In accordance with the Equity Topic in the Accounting Standards Codification ("ASC"), the excess of repurchase price over par value is recorded in retained earnings. Share Repurchase Activity During 2019, 2018, and 2017, CSX repurchased the following shares: Fiscal Years 2019 2018 2017 Shares Repurchased (Units in Millions) 48 72 39 Cost of Shares (Dollars in Millions) $ 3,373 $ 4,671 $ 1,970 Average Price Paid per Share $ 70.54 $ 64.64 $ 50.80 On October 17, 2019, the Company repurchased 4.7 million shares for $319 million from MR Argent Advisor LLC, a CSX shareholder, on behalf of certain limited partners of its affiliated funds (“Mantle Ridge”) under the January 2019 program. A member of CSX’s Board of Directors, Paul C. Hilal, founded and controls Mantle Ridge and each of its related entities. The ownership position of Mantle Ridge is detailed in the Company's Proxy Statement on Schedule 14A filed on March 22, 2019, and subsequent Form 4 filings with the SEC. Shares purchased from Mantle Ridge are included in the table above. In August 2019, the Company entered into an agreement to repurchase shares of the Company’s common stock under the January 2019 program. Under this agreement, the Company made a prepayment of $250 million to a financial institution and settlement occurred in September 2019. At settlement, the Company received approximately 4 million shares, calculated based on the volume-weighted average price of the Company’s common stock over the term of the agreement, less a discount. Shares purchased under this agreement are included in the table above. During 2018, the Company entered into four accelerated share repurchase agreements to repurchase shares of the Company’s common stock under the October 2017 program. Under these agreements, the Company paid $1.5 billion and received approximately 22 million total shares. Shares purchased under accelerated share repurchase agreements are included in the table above.

Shareholders' Equity

Shareholders' Equity	12 Months Ended
Shareholders' Equity	Dec. 31, 2019
Stockholders' Equity Note [Abstract]
Shareholders' Equity	Shareholders’ Equity Common and preferred stock consists of the following: Common Stock, $1 Par Value December 2019 (Units in Millions) Common Shares Authorized 1,800 Common Shares Issued and Outstanding 773 Preferred Stock Preferred Shares Authorized 25 Preferred Shares Issued and Outstanding — Holders of common stock are entitled to one vote on all matters requiring a vote for each share held. Preferred stock is senior to common stock with respect to dividends and upon liquidation of CSX.

Stock Plans and Share-Based Com

Stock Plans and Share-Based Compensation	12 Months Ended
Stock Plans and Share-Based Compensation	Dec. 31, 2019
Share-based Payment Arrangement [Abstract]
Stock Plans and Share-Based Compensation	Stock Plans and Share-Based Compensation Under CSX's share-based compensation plans, awards consist of performance units, stock options, restricted stock units and restricted stock awards for management and stock grants for directors. Awards granted under the various programs are determined and approved by the Compensation Committee of the Board of Directors or, in certain circumstances, by the full Board for awards to the Chief Executive Officer or by the Chief Executive Officer for awards to management employees other than senior executives. The Board of Directors approves awards granted to CSX's non-management directors upon recommendation of the Governance Committee. Share-based compensation expense for awards under share-based compensation plans and purchases made as part of the employee stock purchase plan is measured using the fair value of the award on the grant date and is recognized on a straight-line basis over the service period of the respective award. Forfeitures are recognized as they occur. Total pre-tax expense and income tax benefits associated with share-based compensation are shown in the table below. Income tax benefits include impacts from option exercises and the vesting of other equity awards. Modifications to the terms of awards (see Equity Award Modifications below) impacted share-based compensation expense in 2017. Fiscal Years (Dollars in Millions) 2019 2018 2017 Share-Based Compensation Expense Performance Units $ 42 $ 28 $ 49 Stock Options 18 13 22 Restricted Stock Units and Awards 8 6 15 Stock Awards for Directors 2 2 3 Employee Stock Purchase Plan 4 2 — Total Share-based Compensation Expense $ 74 $ 51 $ 89 Income Tax Benefit $ 43 $ 26 $ 42 NOTE 4. Stock Plans and Share-Based Compensation, continued Long-term Incentive Plans The CSX Long-term Incentive Plans (“LTIP”) were adopted under the 2010 CSX Stock and Incentive Award Plan. On May 3, 2019, shareholders approved the CSX 2019 Stock and Incentive Award Plan, under which future awards will be granted. The objective of these plans is to motivate and reward certain employees for achieving and exceeding certain financial goals. Grants were made in performance units, with each unit being equivalent to one share of CSX common stock, and payouts will be made in CSX common stock. The payout range for most participants will be between 0% and 200% of the target awards depending on Company performance against predetermined goals for each three -year cycle. In 2019, 2018, and 2017, target performance units were granted to certain employees under three separate LTIP plans covering three -year cycles: the 2019-2021 ("2019-2021 LTIP"), the 2018-2020 (“2018-2020 LTIP”), and the 2017-2019 (“2017-2019 LTIP”) plans. The key financial targets for the 2017-2019 LTIP plan are based on the achievement of goals related to both operating ratio and return on assets (tax-adjusted operating income divided by net property) excluding certain items as disclosed in the Company's financial statements. The three -year cumulative operating ratio and average return on assets over the performance period will each comprise 50% of the payout and are measured independently of the other. This plan states that payouts for certain executive officers are subject to downward adjustment by up to 30% based upon total shareholder return relative to specified comparable groups. Payouts of performance units for the 2018-2020 and 2019-2021 LTIP plans will be based on the achievement of goals related to both operating ratio and free cash flow, in each case excluding non-recurring items as disclosed in the Company’s financial statements. For the 2018-2020 LTIP plan, the final year operating ratio and cumulative free cash flow over the plan period will each comprise 50% of the payout and will be measured independently of the other. For the 2019-2021 LTIP plan, the cumulative operating ratio and cumulative free cash flow over the plan period will each comprise 50% of the payout and will be measured independently of the other. For these plans, payouts for certain executive officers are subject to formulaic upward or downward adjustment by up to 25% , capped at an overall payout of 200% for the 2018 plan and 250% for the 2019 plan, based upon the Company’s total shareholder return relative to specified comparable groups over the performance period. The fair value of the performance units awarded during the years ended December 2019 and 2018 were calculated using a Monte-Carlo simulation model with the following weighted-average assumptions: Weighted-average assumptions used: 2019 2018 Annual dividend yield 1.4 % 1.6 % Risk-free interest rate 2.4 % 2.3 % Annualized volatility 27.4 % 29.1 % Expected life (in years) 2.8 2.9 NOTE 4. Stock Plans and Share-Based Compensation, continued Performance unit grant and vesting information is summarized as follows: Fiscal Years 2019 2018 2017 Weighted-average grant date fair value $ 66.18 $ 55.57 $ 49.50 Fair value of units vested in fiscal year ending (in millions) $ 17 $ 14 $ 26 The performance unit activity related to the outstanding long-term incentive plans and corresponding fair value is summarized as follows: Performance Units Outstanding Weighted-Average Fair Value at Grant Date Unvested at December 31, 2018 722 $ 52.58 Granted 337 66.18 Forfeited (75 ) 57.20 Vested (341 ) 49.52 Unvested at December 31, 2019 643 $ 60.58 As of December 2019, there was $23 million of total unrecognized compensation cost related to performance units that is expected to be recognized over a weighted-average period of approximately two years . Stock Options Stock options in 2019, 2018, and 2017 were primarily granted along with the corresponding LTIP plans. Under this program, an employee receives an award that provides the opportunity in the future to purchase CSX shares at the closing market price of the stock on the date the award is granted (the strike price). Options granted in 2019 become exercisable either in equal installments on the anniversary of the grant date over a vesting period (three-year graded), or three years after the grant date (three-year cliff), depending on the individual grant. The options granted in 2018 and 2017 vest three years after the grant date (three-year cliff). All options expire 10 years from the grant date if they are not exercised. The fair value of stock options granted was estimated as of the dates of grant using the Black-Scholes-Merton option model which uses the following assumptions: dividend yield, risk-free interest rate, annualized volatility and expected life. The annual dividend yield is based on the most recent quarterly CSX dividend payment annualized. The risk-free interest rate is based on U.S. Treasury yield curve in effect at the time of grant. The annualized volatility is based on historical volatility of daily CSX stock price returns over a 6.1 year look-back period ending on the grant date. The expected life is calculated using the safe harbor approach due to lack of historical data on CSX options, which is the midpoint between the vesting schedule and contractual term ( 10 years ). In March 2017, the Company granted 9 million stock options to former CEO E. Hunter Harrison at a fair value of $12.88 per option. These options were granted with a 10 -year term and an exercise price equal to the closing market price of the underlying stock on the date of grant. Upon his death in December 2017, all of Mr. Harrison's 9 million options were forfeited. NOTE 4. Stock Plans and Share-Based Compensation, continued Assumptions and inputs used to estimate fair value of stock options are summarized as follows: Fiscal Years 2019 2018 2017 Weighted-average grant date fair value $ 17.87 $ 14.65 $ 12.84 Stock options valuation assumptions: Annual dividend yield 1.3 % 1.5 % 1.5 % Risk-free interest rate 2.4 % 2.6 % 2.2 % Annualized volatility 25.7 % 27.0 % 27.1 % Expected life (in years) 6.1 6.5 6.3 Other pricing model inputs: Weighted-average grant-date market price of CSX stock (strike price) $ 70.01 $ 54.19 $ 49.63 The stock option activity is summarized as follows: Stock Options Outstanding Weighted-Average Exercise Price Weighted-Average Remaining Contractual Life Aggregate Intrinsic Value Outstanding at December 31, 2018 4,673 $ 34.89 Granted 1,187 70.01 Forfeited (212 ) 55.35 Exercised (1,853 ) 24.48 Outstanding at December 31, 2019 3,795 $ 49.78 7.5 $ 87 Exercisable at December 31, 2019 1,026 $ 24.60 6.0 $ 49 Unrecognized compensation expense related to stock options as of December 2019 was $15 million and is expected to be recognized over a weighted-average period of approximately two years . The Company issues new shares upon stock option exercises. There were no significant exercises during 2017 or 2018. Additional information on stock option exercises in 2019 is summarized as follows: (Dollars in Millions) 2019 Intrinsic value of stock options exercised $ 87 Cash received from option exercises $ 45 NOTE 4. Stock Plans and Share-Based Compensation, continued Restricted Stock Grants Restricted stock grants consist of units and awards, each equivalent to one share of CSX stock. Restricted stock units are primarily issued along with corresponding LTIP plans and vest three years after the date of grant. Separately, restricted stock awards generally vest over an employment period of up to five years . Participants receive cash dividend equivalents on the unvested shares during the restriction period. These awards are time-based and not based upon CSX’s attainment of operational targets. Restricted stock grant and vesting information is summarized as follows: Fiscal Years 2019 2018 2017 Weighted-average grant date fair value $ 69.19 $ 62.60 $ 48.35 Fair value of units and awards vested during fiscal year ended (in millions) $ 7 $ 9 $ 8 The restricted stock activity related to the outstanding long-term incentive plans and other awards and corresponding fair value is summarized as follows: Restricted Stock Units and Awards Outstanding Weighted-Average Fair Value at Grant Date Unvested at December 31, 2018 684 $ 39.30 Granted 88 69.19 Forfeited (30 ) 53.28 Vested (315 ) 24.21 Unvested at December 31, 2019 427 $ 57.29 As of December 2019, unrecognized compensation expense for these restricted stock units and awards was approximately $8 million , which will be expensed over a weighted-average remaining period of two years . Equity Award Modifications In 2017, as part of an enhanced severance benefit under the management streamlining and realignment initiative discussed in Note 1, unvested performance units, restricted stock units and stock options for separated employees not eligible for retirement were permitted to vest on a pro-rata basis. Additionally, the terms of unvested equity awards for a former Chief Executive Officer, Michael J. Ward, and a former President, Clarence W. Gooden, were modified prior to their retirements on March 6, 2017 to permit prorated vesting through May 31, 2018. The award modifications impacted approximately 75 employees and resulted in an increase to share-based compensation expense for revaluation of the affected awards of $39 million for the year ended December 31, 2017. The expense associated with these award modifications was included in the 2017 restructuring charge. No significant award modifications took place in 2019 or 2018. NOTE 4. Stock Plans and Share-Based Compensation, continued Stock Awards for Directors CSX’s non-management directors receive a base annual retainer of $112,500 to be paid quarterly in cash, unless the director chooses to defer the retainer in the form of cash or CSX common stock. Additionally, non-management directors receive an annual grant of common stock in the amount of approximately $162,500 , with the number of shares to be granted based on the average closing price of CSX stock in the months of November, December and January. The independent non-executive Chairman also receives an annual grant of common stock in the amount of approximately $250,000 , with the number of shares to be granted based on the average closing price of CSX stock in the months of November, December, and January. Employee Stock Purchase Plan In May 2018, shareholders approved the 2018 CSX Employee Stock Purchase Plan (“ESPP”) for the benefit of Company employees. The Company registered 4 million shares of common stock that may be issued pursuant to this plan. Under the ESPP, employees may contribute between 1% and 10% of base compensation, after-tax, to purchase up to $25,000 of CSX common stock per year at 85% of the closing market price on either the grant date or the last day of the six -month offering period, whichever is lower. During 2019, the Company issued approximately 250 thousand shares under the ESPP.

Casualty, Environmental and Oth

Casualty, Environmental and Other Reserves	12 Months Ended
Casualty, Environmental and Other Reserves	Dec. 31, 2019
Casualty, Environmental and Other Reserves [Abstract]
Casualty, Environmental and Other Reserves	Casualty, Environmental and Other Reserves Activity related to casualty, environmental and other reserves is as follows: Casualty Environmental Other (Dollars in Millions) Reserves Reserves Reserves Total December 30, 2016 $ 229 $ 95 $ 50 $ 374 Charged to Expense 43 26 45 114 Payments (44 ) (31 ) (39 ) (114 ) December 31, 2017 228 90 56 374 Charged to Expense 21 10 41 72 Payments (50 ) (20 ) (52 ) (122 ) December 31, 2018 199 80 45 324 Charged to Expense 56 17 34 107 Payments (68 ) (23 ) (35 ) (126 ) December 31, 2019 $ 187 $ 74 $ 44 $ 305 NOTE 5. Casualty, Environmental and Other Reserves, continued Personal injury and environmental reserves are considered critical accounting estimates due to the need for management judgment. In the table above, the impacts of changes in estimates are included in the charged to expense amount and were not material in 2019, 2018, or 2017. Casualty, environmental and other reserves are provided for in the consolidated balance sheets as shown in the table below. December 2019 December 2018 (Dollars in Millions) Current Long-term Total Current Long-term Total Casualty: Personal Injury $ 42 $ 87 $ 129 $ 40 $ 103 $ 143 Occupational 6 52 58 10 46 56 Total Casualty $ 48 $ 139 $ 187 $ 50 $ 149 $ 199 Environmental 31 43 74 39 41 80 Other 21 23 44 24 21 45 Total $ 100 $ 205 $ 305 $ 113 $ 211 $ 324 These liabilities are accrued when probable and reasonably estimable in accordance with the Contingencies Topic in the ASC. Actual settlements and claims received could differ and final outcomes of these matters cannot be predicted with certainty. Considering the legal defenses currently available, the liabilities that have been recorded and other factors, it is the opinion of management that none of these items individually, when finally resolved, will have a material adverse effect on the Company's financial condition, results of operations or liquidity. Should a number of these items occur in the same period, however, their combined effect could be material in that particular period. Casualty Casualty reserves of $187 million and $199 million for 2019 and 2018 , respectively, represent accruals for personal injury, occupational disease and occupational injury claims. The Company increased its self-insured retention amount for these claims from $50 million to $75 million per occurrence for claims occurring on or after June 1, 2018. Currently, no individual claim is expected to exceed the self-insured retention amount. Most of the Company's casualty claims relate to CSXT. In accordance with the Contingencies Topic in the ASC, to the extent the value of an individual claim exceeds the self-insured retention amount, the Company would present the liability on a gross basis with a corresponding receivable for insurance recoveries. These reserves fluctuate based upon the timing of payments as well as changes in estimate. Actual results may vary from estimates due to the number, type and severity of the injury, costs of medical treatments and uncertainties in litigation. Defense and processing costs, which historically have been insignificant and are anticipated to be insignificant in the future, are not included in the recorded liabilities. Changes in casualty reserves are included in materials, supplies and other on the consolidated income statements. NOTE 5. Casualty, Environmental and Other Reserves, continued Personal Injury Personal injury reserves represent liabilities for employee work-related and third-party injuries. Work-related injuries for CSXT employees are primarily subject to the Federal Employers' Liability Act ("FELA"). CSXT retains an independent actuary to assist management in assessing the value of personal injury claims. An analysis is performed by the actuary quarterly and is reviewed by management. The methodology used by the actuary includes a development factor to reflect growth or reduction in the value of these personal injury claims based largely on CSXT's historical claims and settlement experience. This analysis did not result in a material adjustment to the personal injury reserve in 2019, 2018 or 2017. Occupational Occupational reserves represent liabilities for occupational disease and injury claims. Occupational disease claims arise primarily from allegations of exposure to asbestos in the workplace. Occupational injury claims arise from allegations of exposure to certain other materials in the workplace, such as solvents, soaps, chemicals (collectively referred to as “irritants”) and diesel fuels (like exhaust fumes) or allegations of chronic physical injuries resulting from work conditions, such as repetitive stress injuries. An analysis performed by management did not result in a material adjustment to the occupational reserve in 2019, 2018 or 2017. Environmental Environmental reserves were $74 million and $80 million for 2019 and 2018 , respectively. The Company is a party to various proceedings related to environmental issues, including administrative and judicial proceedings involving private parties and regulatory agencies. The Company has been identified as a potentially responsible party at approximately 220 environmentally impaired sites. Many of these are, or may be, subject to remedial action under the federal Comprehensive Environmental Response, Compensation and Liability Act of 1980 ("CERCLA"), also known as the Superfund Law, or similar state statutes. Most of these proceedings arose from environmental conditions on properties used for ongoing or discontinued railroad operations. A number of these proceedings, however, are based on allegations that the Company, or its predecessors, sent hazardous substances to facilities owned or operated by others for treatment, recycling or disposal. In addition, some of the Company’s land holdings were leased to others for commercial or industrial uses that may have resulted in releases of hazardous substances or other regulated materials onto the property and could give rise to proceedings against the Company. In any such proceedings, the Company is subject to environmental clean-up and enforcement actions under the Superfund Law, as well as similar state laws that may impose joint and several liability for clean-up and enforcement costs on current and former owners and operators of a site without regard to fault or the legality of the original conduct. These costs could be substantial. NOTE 5. Casualty, Environmental and Other Reserves, continued In accordance with the Asset Retirement and Environmental Obligations Topic in the ASC, the Company reviews its role with respect to each site identified at least quarterly, giving consideration to a number of factors such as: • type of clean-up required; • nature of the Company’s alleged connection to the location (e.g., generator of waste sent to the site or owner or operator of the site); • extent of the Company’s alleged connection (e.g., volume of waste sent to the location and other relevant factors); and • number, connection and financial viability of other named and unnamed potentially responsible parties at the location. Based on the review process, the Company has recorded amounts to cover contingent anticipated future environmental remediation costs with respect to each site to the extent such costs are reasonably estimable and probable. The recorded liabilities for estimated future environmental costs are undiscounted. The liability includes future costs for remediation and restoration of sites as well as any significant ongoing monitoring costs, but excludes any anticipated insurance recoveries. Payments related to these liabilities are expected to be made over the next several years. Environmental remediation costs are included in materials, supplies and other on the consolidated income statements. Currently, the Company does not possess sufficient information to reasonably estimate the amounts of additional liabilities, if any, on some sites until completion of future environmental studies. In addition, conditions that are currently unknown could, at any given location, result in additional exposure, the amount and materiality of which cannot presently be reasonably estimated. Based upon information currently available, however, the Company believes its environmental reserves accurately reflect the estimated cost of remedial actions currently required. Other Other reserves were $44 million and $45 million for 2019 and 2018 , respectively. These reserves include liabilities for various claims, such as property, automobile and general liability. Also included in other reserves are longshoremen disability claims related to a previously owned international shipping business (these claims are in runoff) as well as claims for current port employees.

Properties

Properties	12 Months Ended
Properties	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Properties	Properties A detail of the Company’s net properties are as follows: (Dollars in Millions) Accumulated Net Book Annual Depreciation Estimated Useful Life Depreciation December 2019 Cost Depreciation Value Rate ( Avg. Years) Method Road Rail and Other Track Material $ 8,194 $ (1,719 ) $ 6,475 2.5% 40 Group Life Ties 6,041 (1,666 ) 4,375 3.7% 27 Group Life Grading 2,763 (595 ) 2,168 1.4% 72 Group Life Ballast 3,156 (1,013 ) 2,143 2.7% 37 Group Life Bridges, Trestles, and Culverts 2,529 (334 ) 2,195 1.6% 61 Group Life Signals and Interlockers 3,077 (819 ) 2,258 4.0% 25 Group Life/ Straight Line (a) Buildings 1,335 (492 ) 843 2.5% 40 Group Life Other 5,030 (1,980 ) 3,050 4.2% 24 Group Life Total Road 32,125 (8,618 ) 23,507 Equipment Locomotive 5,320 (2,020 ) 3,300 3.6% 27 Group Life Freight Cars 2,964 (880 ) 2,084 2.9% 35 Group Life Work Equipment and Other 2,424 (1,414 ) 1,010 8.2% 12 Group Life/ Straight Line (a) Total Equipment 10,708 (4,314 ) 6,394 Land 1,836 — 1,836 N/A N/A N/A Construction In Progress 431 — 431 N/A N/A N/A Total Properties $ 45,100 $ (12,932 ) $ 32,168 (a) For depreciation method, certain asset categories contain intermodal terminals or technology-related assets, which are depreciated using the straight-line method. NOTE 6. Properties, continued (Dollars in Millions) Accumulated Net Book Annual Depreciation Estimated Useful Life Depreciation December 2018 Cost Depreciation Value Rate (Avg. Years) Method Road Rail and Other Track Material $ 7,964 $ (1,698 ) $ 6,266 2.5% 40 Group Life Ties 5,860 (1,557 ) 4,303 3.7% 27 Group Life Grading 2,757 (572 ) 2,185 1.4% 72 Group Life Ballast 3,076 (971 ) 2,105 2.7% 37 Group Life Bridges, Trestles, and Culverts 2,506 (382 ) 2,124 1.6% 61 Group Life Signals and Interlockers 2,975 (693 ) 2,282 4.0% 25 Group Life/ Straight Line (a) Buildings 1,318 (486 ) 832 2.5% 40 Group Life Other 4,955 (1,964 ) 2,991 4.2% 24 Group Life Total Road 31,411 (8,323 ) 23,088 Equipment Locomotive 5,661 (2,266 ) 3,395 3.5% 29 Group Life Freight Cars 3,093 (882 ) 2,211 2.9% 35 Group Life Work Equipment and Other 2,338 (1,336 ) 1,002 7.4% 14 Group Life/ Straight Line (a) Total Equipment 11,092 (4,484 ) 6,608 Land 1,845 — 1,845 N/A N/A N/A Construction In Progress 457 — 457 N/A N/A N/A Total Properties $ 44,805 $ (12,807 ) $ 31,998 (a) For depreciation method, certain asset categories contain intermodal terminals or technology-related assets, which are depreciated using the straight-line method. NOTE 6. Properties, continued Capital Expenditures The Company’s capital investment includes purchased and self-constructed assets and property additions that substantially extend the service life or increase the utility of those assets. Indirect costs that can be specifically traced to capital projects are also capitalized. The Company is committed to maintaining and improving its existing infrastructure and expanding its network capacity for long-term growth. Rail operations are capital intensive and CSX accounts for these costs in accordance with GAAP and the Company’s capitalization policy. All properties are stated at historical cost less an allowance for accumulated depreciation. The Company’s largest category of capital investment is the replacement of track assets and the acquisition or construction of new assets that enable CSX to enhance its operations or provide new capacity offerings to its customers. These construction projects are primarily completed by CSXT employees. Costs for track asset replacement and capacity projects that are capitalized include: • labor costs, because many of the assets are self-constructed; • costs to purchase or construct new track or to prepare ground for the laying of track; • welding (rail, field and plant) which are processes used to connect segments of rail; • new ballast, which is gravel and crushed stone that holds track in line; • fuels and lubricants associated with tie, rail and surfacing work which is the process of raising track to a designated elevation over an extended distance; • cross, switch and bridge ties which are the braces that support the rails on a track; • gauging which is the process of standardizing the distance between rails; • handling costs associated with installing rail, ties or ballast; • usage charge of machinery and equipment utilized in construction or installation; and • other track materials. Labor is a significant cost in self-constructed track replacement work. CSXT engineering employees directly charge their labor to the track replacement project (the capitalized depreciable property). In replacing track, these employees concurrently perform deconstruction and installation of track material. Because of this concurrent process, CSX must estimate the amount of labor that is related to deconstruction versus installation. As a component of the depreciation study for road and track assets, management performs an analysis of labor costs related to the self-constructed track replacement work, which includes direct observation of track replacement processes. Through this analysis, CSX determined that approximately 20% of labor costs associated with track replacement is related to the deconstruction of old track, for which certain elements are expensed, and 80% is associated with the installation of new track, which is capitalized. Capital investment related to locomotives and freight cars comprises the second largest category of the Company’s capital assets. This category includes purchases of locomotives and freight cars as well as certain equipment leases that are considered to be finance leases in accordance with the Leases Topic in the ASC. In addition, costs to modify or rebuild these assets are capitalized if the investment incurred extends the asset’s service life or improves utilization. Improvement projects must meet specified dollar thresholds to be capitalized and are reviewed by management to determine proper accounting treatment. Routine repairs, overhauls and other maintenance costs, for all asset categories, are expensed as incurred. NOTE 6. Properties, continued Depreciation Method The depreciable assets of the Company are depreciated using either the group-life or straight-line method of accounting, which are both acceptable depreciation methods in accordance with GAAP. The Company depreciates its railroad assets, including main-line track, locomotives and freight cars, using the group-life method. Assets depreciated under the group-life method comprise 87% of total fixed assets of $45.1 billion on a gross basis as of December 2019. The remaining depreciable assets of the Company, including non-railroad assets and assets under finance leases, are depreciated using the straight-line method on a per asset basis. Land is not depreciated. The group-life method aggregates assets with similar lives and characteristics into groups and depreciates each of these groups as a whole. When using the group-life method, an underlying assumption is that each group of assets, as a whole, is used and depreciated to the end of its group’s recoverable life. The Company currently utilizes different depreciable asset categories to account for depreciation expense for the railroad assets that are depreciated under the group-life method. By utilizing various depreciable categories, the Company can more accurately account for the use of its assets. All assets of the Company are depreciated on a time or life basis. The group-life method of depreciation closely approximates the straight-line method of depreciation. Additionally, due to the nature of most of its assets (e.g. track is one contiguous, connected asset), the Company believes that this is the most accurate and effective way to properly depreciate its assets. Estimated Useful Life Management performs a review of depreciation expense and useful lives on a regular basis. Under the group-life method, the service lives and salvage values for each group of assets are determined by completing periodic depreciation studies and applying management’s methods to determine the service lives of its properties. A depreciation study is the periodic review of asset service lives, salvage values, accumulated depreciation, and other related factors for group assets conducted by a third-party specialist, analyzed by the Company’s management and approved by the STB, the regulatory board that has broad jurisdiction over railroad practices. The STB requires depreciation studies be performed every three years for equipment assets (e.g. locomotives and freight cars) and every six years for road and track assets (e.g. bridges, signals, rail, ties, and ballast). The Company believes the frequency of depreciation studies currently required by the STB, complemented by annual data reviews conducted by a third-party specialist and analyzed by the Company's management, provides adequate review of asset service lives and that a more frequent review would not result in a material change due to the long-lived nature of most of the assets. In 2019, the Company completed a depreciation study for its equipment assets which resulted in changes to accumulated depreciation, service lives, salvage values, and other related factors for certain assets. The effect of this change in estimate was not material to depreciation expense in 2019. The continued impacts of the study are expected to result in additional depreciation expense of approximately $30 million in 2020. The Company plans to complete the next depreciation study for road and track assets in 2020 and equipment assets in 2022. NOTE 6. Properties, continued Group-Life Assets Sales and Retirements Since the rail network is one contiguous, connected network it is impractical to maintain specific identification records for these assets. For track assets (e.g. rail, ties, and ballast), CSX utilizes a first-in, first-out approach to asset retirements. Equipment assets (e.g. locomotives and freight cars) are specifically identified at retirement. When an equipment asset is retired that has been depreciated using the group-life method, the cost is reduced from the cost base and recorded in accumulated depreciation. For sales or retirements of assets depreciated under the group-life method that occur in the ordinary course of business, the asset cost (net of salvage value or sales proceeds) is charged to accumulated depreciation and no gain or loss is immediately recognized. This practice is consistent with accounting treatment prescribed under the group-life method. As part of the depreciation study, an assessment of the recorded amount of accumulated depreciation is made to determine if it is deficient (or in excess) of the appropriate amount indicated by the study. Any such deficiency (or excess), including any deferred gains or losses, is amortized as a component of depreciation expense over the remaining service life of the asset group until the next required depreciation study. Since the overall assumption with the group-life method is that the assets within the group on average have the same service life and characteristics, it is therefore concluded that the deferred gains and losses offset over time. For sales or retirements of assets depreciated under the group-life method that do not occur in the ordinary course of business, a gain or loss may be recognized if the sale or retirement meets each of the following three criteria: (i) it is unusual, (ii) it is material in amount, and (iii) it varies significantly from the retirement profile identified through our depreciation studies. No material gains or losses were recognized on the sale of assets depreciated using the group-life method in 2019, 2018, or 2017 as no sales met the criteria described above. Land and Straight-line Assets Sales and Retirements When the Company sells or retires land, land-related easements or assets depreciated under the straight-line method, a gain or loss is recognized in materials, supplies and other on the consolidated statements of income. In 2019, the Company recognized gains on the sale of properties of $151 million as a result of its initiative to monetize non-core properties. In 2018 and 2017, the Company recognized gains on the sale of properties of $154 million and $18 million , respectively. Impairment Review Properties and other long-lived assets are reviewed for impairment whenever events or business conditions indicate the carrying amount of such assets may not be fully recoverable. Initial assessments of recoverability are based on estimates of undiscounted future net cash flows associated with an asset or a group of assets in accordance with the Property, Plant, and Equipment Topic in the ASC. Where impairment is indicated, the assets are evaluated and their carrying amount is reduced to fair value based on discounted net cash flows or other estimates of fair value. In 2019, impairment expense of $22 million was related to an intermodal terminal sale agreement. In 2018 and 2017, impairment expense of $24 million and $25 million , respectively, was primarily due to the discontinuation of certain in-progress projects. Impairment expense is recorded in materials, supplies and other expense on the consolidated income statement.

Leases

Leases	12 Months Ended
Leases	Dec. 31, 2019
Leases [Abstract]
Leases	Leases CSX has various lease agreements with terms up to 50 years , including leases of land, land with integral equipment (e.g. track), buildings and various equipment. Some leases include options to purchase, terminate or extend for one or more years. These options are included in the lease term when it is reasonably certain that the option will be exercised. At inception, the Company determines if an arrangement contains a lease and whether that lease meets the classification criteria of a finance or operating lease. Some of the Company’s lease arrangements contain lease components (e.g. minimum rent payments) and non-lease components (e.g. maintenance, labor charges, etc.). The Company generally accounts for each component separately based on the estimated standalone price of each component. For certain equipment leases, such as freight car, vehicles and work equipment, the Company accounts for the lease and non-lease components as a single lease component. Certain of the Company’s lease agreements include rental payments that are adjusted periodically for an index or rate. The leases are initially measured using the projected payments adjusted for the index or rate in effect at the commencement date. The Company’s lease agreements do not contain any material residual value guarantees or material restrictive covenants. Operating Leases Operating leases are included in right-of-use lease assets, other current liabilities and long-term lease liabilities on the consolidated balance sheets. These assets and liabilities are recognized at the commencement date based on the present value of remaining lease payments over the lease term using the Company’s secured incremental borrowing rates or implicit rates, when readily determinable. Short-term operating leases, which have an initial term of 12 months or less, are not recorded on the balance sheet. The Company has various lease agreements with other parties with terms up to 50 years . Non-cancelable, long-term leases may include provisions for maintenance, options to purchase and options to extend the terms. Lease expense for operating leases, including leases with escalations over their terms, is recognized on a straight-line basis over the lease term. Variable lease expense is recognized in the period in which the obligation for those payments is incurred. Lease expense is included in equipment and other rents on the consolidated income statements and is reported net of lease income. Lease income was not material to the results of operations for 2019, 2018 or 2017. NOTE 7. Leases, continued A significant operating lease was renewed in 2018 with the State of Georgia for approximately 137 miles of right-of-way with integral equipment for an additional term of 50 years with an annual 2.5% increase. The following table presents information about the amount, timing and uncertainty of cash flows arising from the Company’s operating leases as of December 31, 2019 . (Dollars in Millions) December 2019 Maturity of Lease Liabilities Lease Payments 2020 58 2021 54 2022 48 2023 39 2024 37 Thereafter 1,208 Total undiscounted operating lease payments $ 1,444 Less: Imputed interest (894 ) Present value of operating lease liabilities $ 550 Balance Sheet Classification Current lease liabilities (recorded in other current liabilities) $ 57 Long-term lease liabilities 493 Total operating lease liabilities $ 550 Other Information Weighted-average remaining lease term for operating leases 33 years Weighted-average discount rate for operating leases 5.0 % Cash Flows An initial right-of-use asset of $534 million was recognized as a non-cash asset addition upon adoption of the new lease accounting standard effective January 1, 2019. Additional right-of-use assets of $51 million were recognized as non-cash asset additions that resulted from new operating lease liabilities during the year ended December 31, 2019. Cash paid for amounts included in the present value of operating lease liabilities was $60 million during the year ended December 31, 2019 and is included in operating cash flows. Operating Lease Costs These costs are primarily related to long-term operating leases, but also include immaterial amounts for variable leases and short-term leases with terms greater than 30 days. These amounts are shown in the table below. Fiscal Years (Dollars in Millions) 2019 2018 2017 Rent Expense on Operating Leases $ 84 $ 66 $ 78 NOTE 7. Leases, continued Finance Leases Finance leases are included in properties-net and long-term debt on the consolidated balance sheets and were not material as of December 2019 or December 2018. The associated amortization expense and interest expense are included in depreciation and interest expense, respectively, on the consolidated income statements and were not material to the results of operations for 2019, 2018 or 2017.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Purchase Commitments CSXT's long-term locomotive maintenance program agreement with a third-party contains commitments related to specific locomotive rebuilds and a long-term maintenance program that covers a portion of CSXT’s fleet of locomotives. The maintenance program costs are based on the maintenance cycle for each covered locomotive, which is determined by the asset's age and type. Expected future costs may change as required maintenance schedules are revised and locomotives are placed into or removed from service. Under CSXT’s current obligations, the agreement will expire no earlier than 2035. The following table summarizes the number of locomotives covered and CSXT’s payments under the long-term maintenance program. Fiscal Years (Dollars in Millions) 2019 2018 2017 Amounts Paid $ 139 $ 170 $ 197 Number of Locomotives 1,897 1,910 2,062 The total of annual payments under the agreement, including those related to locomotive rebuilds and the long-term locomotive maintenance program, are estimated in the table below. Additionally, the Company has various other commitments to purchase technology, communications, railcar maintenance and other services from various suppliers. Total annual payments under all of these purchase commitments are also estimated in the table below. (Dollars in Millions) Locomotive Maintenance & Rebuild Payments Other Commitments Total 2020 $ 233 $ 59 $ 292 2021 178 19 197 2022 211 18 229 2023 237 17 254 2024 273 17 290 Thereafter 2,337 111 2,448 Total $ 3,469 $ 241 $ 3,710 NOTE 8. Commitments and Contingencies, continued Insurance The Company maintains insurance programs with substantial limits for property damage (which includes business interruption) and third-party liability. A certain amount of risk is retained by the Company on each of the property and liability programs. The Company has a $50 million per occurrence retention for floods and named windstorms and a $25 million per occurrence retention for property losses other than floods and named windstorms. For claims occurring on or after June 1, 2018, the Company increased its self-insured retention for third-party liability claims from $50 million to $75 million per occurrence. While the Company believes its insurance coverage is adequate, future claims could exceed existing insurance coverage or insurance may not continue to be available at commercially reasonable rates. Legal The Company is involved in litigation incidental to its business and is a party to a number of legal actions and claims, various governmental proceedings and private civil lawsuits, including, but not limited to, those related to fuel surcharge practices, tax matters, environmental and hazardous material exposure matters, FELA and labor claims by current or former employees, other personal injury or property claims and disputes and complaints involving certain transportation rates and charges. Some of the legal proceedings include claims for compensatory as well as punitive damages and others are, or are purported to be, class actions. While the final outcome of these matters cannot be predicted with certainty, considering, among other things, the legal defenses available and liabilities that have been recorded along with applicable insurance, it is currently the opinion of management that none of these pending items will have a material adverse effect on the Company's financial condition, results of operations or liquidity. An unexpected adverse resolution of one or more of these items, however, could have a material adverse effect on the Company's financial condition, results of operations or liquidity in that particular period. The Company is able to estimate a range of possible loss for certain legal proceedings for which a loss is reasonably possible in excess of reserves established. The Company has estimated this range to be $1 million to $29 million in aggregate at December 31, 2019 . This estimated aggregate range is based upon currently available information and is subject to significant judgment and a variety of assumptions. Accordingly, the Company's estimate will change from time to time, and actual losses may vary significantly from the current estimate. Fuel Surcharge Antitrust Litigation In May 2007, class action lawsuits were filed against CSXT and three other U.S.-based Class I railroads alleging that the defendants' fuel surcharge practices relating to contract and unregulated traffic resulted from an illegal conspiracy in violation of antitrust laws. The class action lawsuits were consolidated into one case in federal court in the District of Columbia. In 2017, the District Court issued its decision denying class certification. On August 16, 2019, the U.S. Court of Appeals for the D.C. Circuit affirmed the District Court’s ruling. The District Court had delayed proceedings on the merits of the consolidated case pending the outcome of the class certification proceedings. The consolidated case is now moving forward without class certification. Because a class was not certified, shippers other than those who brought the original lawsuit in 2007 must decide whether to bring their own individual claim against one or more railroads. Some individual shipper claims have been filed. NOTE 8. Commitments and Contingencies, continued CSXT believes that its fuel surcharge practices were arrived at and applied lawfully and that the case is without merit. Accordingly, the Company intends to defend itself vigorously. However, penalties for violating antitrust laws can be severe, and resolution of these matters individually or when aggregated could have a material adverse effect on the Company's financial condition, results of operations or liquidity in that particular period. Environmental CSXT is indemnifying Pharmacia LLC (formerly known as Monsanto Company) for certain liabilities associated with real estate located in Kearny, New Jersey along the Lower Passaic River (the “Property”). The Property, which was formerly owned by Pharmacia, is now owned by CSXT. CSXT's indemnification and defense duties arise with respect to several matters. The U.S. Environmental Protection Agency ("EPA"), using its CERCLA authority, seeks the investigation and cleanup of hazardous substances in the 17 -mile Lower Passaic River Study Area (the "Study Area”). CSXT, on behalf of Pharmacia, and a significant number of other potentially responsible parties are together conducting a Remedial Investigation and Feasibility Study of the Study Area pursuant to an Administrative Settlement Agreement and Order on Consent with the EPA. Pharmacia’s share of responsibility, indemnified by CSXT, for the investigation and cleanup costs of the Study Area may be determined through various mechanisms including (a) an allocation and settlement with EPA; (b) litigation brought by EPA against non-settling parties; or (c) litigation among the responsible parties. In March 2016, EPA issued its Record of Decision detailing the agency’s mandated remedial process for the lower 8 miles of the Study Area. Approximately 80 parties, including Pharmacia, are participating in an EPA-directed allocation process to assign responsibility for costs to be incurred implementing the remedy selected for the lower 8 miles of the Study Area. CSXT is participating in the allocation process on behalf of Pharmacia. At a later date, EPA will select a remedy for the remainder of the Study Area and is expected to again seek the participation of private parties to implement the selected remedy using EPA’s CERCLA authority to compel such participation, if necessary. CSXT is also defending and indemnifying Pharmacia with regard to the Property in litigation filed by Occidental Chemical Corporation, which is seeking to recover various costs. These costs include costs for the remedial design of the lower 8 miles of the Study Area, as well as anticipated costs associated with the future remediation of the lower 8 miles of the Study Area and potentially the entire Study Area. Alternatively, Occidental seeks to compel some, or all of the defendants to participate in the remediation of the Study Area. Pharmacia is one of approximately 110 defendants in this federal lawsuit filed by Occidental on June 30, 2018.

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
Employee Benefit Plans	Dec. 31, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]
Employee Benefit Plans	Employee Benefit Plans The Company sponsors defined benefit pension plans principally for salaried, management personnel. For employees hired prior to 2003 , the plans provide eligible employees with retirement benefits based predominantly on years of service and compensation rates near retirement. For employees hired in 2003 to 2019 , benefits are determined based on a cash balance formula, which provides benefits by utilizing interest and pay credits based upon age, service and compensation. Beginning in 2020, the CSX Pension Plan is closed to new participants. In addition to these plans, the Company sponsors a post-retirement medical plan and a life insurance plan that provide certain benefits to full-time, salaried, management employees hired prior to 2003 , upon their retirement if certain eligibility requirements are met. Changes to the post-retirement medical and life insurance plans were communicated to participants in October 2018. Beginning January 2019, both the life insurance benefit for eligible active employees and health savings account contributions made by the Company to eligible retirees younger than 65 were eliminated. Beginning in 2020, the employer-funded health reimbursement arrangements for eligible retirees 65 years or older have been eliminated. As a result of these plan amendments, the company recognized a decrease of $102 million in the post-retirement benefit liability and a corresponding gain in other comprehensive income in 2018. These changes did not result in a curtailment loss as there was no material impact to service costs for active plan participants. The Company engages independent actuaries to compute the amounts of liabilities and expenses relating to these plans subject to the assumptions that the Company determines are appropriate based on historical trends, current market rates and future projections. These amounts are reviewed by management. In order to perform this valuation, the actuaries are provided with the details of the population covered at the beginning of the year, summarized in the table below, and projects that population forward to the end of the year . Summary of Participants as of January 1, 2019 Pension Plans Post-retirement Medical Plan Active Employees 3,521 616 Retirees and Beneficiaries 12,016 8,393 Other (a) 4,012 40 Total 19,549 9,049 (a) For pension plans, the other category consists mostly of terminated but vested former employees. For post-retirement plans, the other category consists of employees on long-term disability that have not yet retired. NOTE 9. Employee Benefit Plans, continued The benefit obligation for these plans represents the liability of the Company for current and retired employees and is affected primarily by the following: • service cost (benefits attributed to employee service during the period); • interest cost (interest on the liability due to the passage of time); • actuarial gains/losses (experience during the year different from that assumed and changes in plan assumptions); and • benefits paid to participants. Cash Flows Plan assets are amounts that have been segregated and restricted to provide qualified pension plan benefits and include amounts contributed by the Company and amounts earned from invested contributions, net of benefits paid. Qualified pension plan obligations are funded in accordance with regulatory requirements and with an objective of meeting or exceeding minimum funding requirements necessary to avoid restrictions on flexibility of plan operation and benefit payments. The Company funds the cost of the post-retirement medical and life insurance benefits as well as nonqualified pension benefits on a pay-as-you go basis. No qualified pension plan contributions were made during 2019, 2018 and 2017. No contributions to the Company's qualified pension plans are expected in 2020 . Future expected benefit payments are as follows: Expected Cash Flows (Dollars in Millions) Pension Benefits Post-retirement Benefits 2020 $ 193 $ 20 2021 188 12 2022 186 10 2023 184 9 2024 182 9 2025-2029 897 34 Total $ 1,830 $ 94 NOTE 9. Employee Benefit Plans, continued Plan Assets The CSX Investment Committee (the “Investment Committee”), whose members are selected by the Chief Financial Officer, is responsible for oversight and investment of plan assets. The Investment Committee utilizes an investment asset allocation strategy that is monitored on an ongoing basis and updated periodically in consideration of plan or employee changes, or changing market conditions. Periodic studies provide an extensive modeling of asset investment return in conjunction with projected plan liabilities and seek to evaluate how to maximize return within the constraints of acceptable risk. The current asset allocation targets 60% equity investments and 40% fixed income investments and cash. Within equity, a further target is currently established for 37% of total plan assets in domestic equity and 23% in international equity. Allocations are evaluated for levels within 3% of targeted allocations and are adjusted quarterly as necessary. The distribution of pension plan assets as of the measurement date is shown in the table below, and these assets are reported net of pension liabilities on the balance sheet. December 2019 December 2018 Percent of Percent of (Dollars in Millions) Amount Total Assets Amount Total Assets Equity $ 1,770 63 % $ 1,698 70 % Fixed Income 818 29 704 29 Cash and Cash Equivalents 237 8 29 1 Total $ 2,825 100 % $ 2,431 100 % Under the supervision of the Investment Committee, individual investments or fund managers are selected in accordance with standards of prudence applicable to asset diversification and investment suitability. The Company also selects fund managers with differing investment styles and benchmarks their investment returns against appropriate indices. Fund investment performance is continuously monitored. Acceptable performance is determined in the context of the long-term return objectives of the fund and appropriate asset class benchmarks. Within the Company's equity funds, domestic stock is diversified among large and small capitalization stocks. International stock is diversified in a similar manner as well as in developed versus emerging markets stocks. Guidelines established with individual managers limit investment by industry sectors, individual stock issuer concentration and the use of derivatives and CSX securities. Fixed income securities guidelines established with individual managers specify the types of allowable investments, such as government, corporate and asset-backed bonds, target certain allocation ranges for domestic and foreign investments and limit the use of certain derivatives. Additionally, guidelines stipulate minimum credit quality constraints and any prohibited securities. For detailed information regarding the fair value of pension assets, see Note 13, Fair Value Measurements . NOTE 9. Employee Benefit Plans, continued Benefit Obligation, Plan Assets and Funded Status Changes in benefit obligation and the fair value of plan assets for the 2019 and 2018 calendar plan years are as follows: Pension Benefits Post-retirement Benefits Plan Year Plan Year Plan Year Plan Year (Dollars in Millions) 2019 2018 2019 2018 Actuarial Present Value of Benefit Obligation Accumulated Benefit Obligation $ 2,963 $ 2,623 N/A N/A Projected Benefit Obligation 3,122 2,758 $ 117 $ 118 Change in Projected Benefit Obligation: Projected Benefit Obligation at Beginning of Plan Year $ 2,758 $ 3,002 $ 118 $ 250 Service Cost (a) 34 36 1 2 Interest Cost 103 92 2 7 Plan Participants' Contributions — — 7 5 Post-retirement Plan Amendment — — — (102 ) Actuarial Loss (Gain) 418 (173 ) 22 (10 ) Benefits Paid (191 ) (199 ) (33 ) (34 ) Benefit Obligation at End of Plan Year $ 3,122 $ 2,758 $ 117 $ 118 Change in Plan Assets: Fair Value of Plan Assets at Beginning of Plan Year $ 2,431 $ 2,833 $ — $ — Actual Return on Plan Assets Gain (Loss) 568 (220 ) — — Non-qualified Employer Contributions 17 17 26 30 Plan Participants' Contributions — — 7 4 Benefits Paid (191 ) (199 ) (33 ) (34 ) Fair Value of Plan Assets at End of Plan Year 2,825 2,431 — — Funded Status at End of Plan Year $ (297 ) $ (327 ) $ (117 ) $ (118 ) (a) Service cost for each 2019 and 2018 includes capitalized service costs of $3 million . NOTE 9. Employee Benefit Plans, continued For qualified plan funding purposes, assets and discounted liabilities are measured in accordance with the Employee Retirement Income Security Act ("ERISA"), as well as other related provisions of the Internal Revenue Code and related regulations. Under these funding provisions and the alternative measurements available thereunder, the Company estimates its unfunded obligation for qualified plans on an annual basis. In accordance with Compensation-Retirement Benefits Topic in the ASC, an employer must recognize the funded status of a pension or other post-retirement benefit plan by recording a liability (underfunded plan) or asset (overfunded plan) for the difference between the projected benefit obligation (or the accumulated post-retirement benefit obligation for a post-retirement benefit plan) and the fair value of plan assets at the plan measurement date. Amounts related to pension and post-retirement benefits recorded in other long-term assets, labor and fringe benefits payable and other long-term liabilities on the balance sheet are as follows: Pension Benefits Post-retirement Benefits December December December December (Dollars in Millions) 2019 2018 2019 2018 Amounts Recorded in Consolidated Balance Sheets: Long-term Assets (a) $ 25 $ 13 $ — $ — Current Liabilities (17 ) (16 ) (20 ) (34 ) Long-term Liabilities (305 ) (324 ) (97 ) (84 ) Net Amount Recognized in Consolidated Balance Sheets $ (297 ) $ (327 ) $ (117 ) $ (118 ) (a) Long-term assets as of December 2019 and 2018 relate to qualified pension plans where assets exceed projected benefit obligations. The funded status, or amount by which the benefit obligation exceeds the fair value of plan assets, represents a liability. At December 2019, the status of CSX plans with a net liability only is disclosed below. The total fair value of all plan assets as of December 2019 was $2.8 billion , which includes the qualified pension plans with net assets. Aggregate (Dollars in Millions) Fair Value Aggregate Benefit Obligations in Excess of Plan Assets of Plan Assets Benefit Obligation Projected Benefit Obligation $ 2,715 $ (3,037 ) Accumulated Benefit Obligation 2,715 (2,878 ) NOTE 9. Employee Benefit Plans, continued Net Benefit Expense Only the service cost component of net periodic benefit costs is included in labor and fringe expense on the consolidated income statement. All other components of net periodic benefit cost are included in other income - net or, if related to prior year restructuring activities, in restructuring charge - non-operating. The following table describes the components of expense/(income) related to net benefit expense recorded on the income statement. Pension Benefits Fiscal Years Post-retirement Benefits Fiscal Years (Dollars in Millions) 2019 2018 2017 2019 2018 2017 Service Cost Included in Labor and Fringe $ 31 $ 32 $ 36 $ 1 $ 2 $ 2 Interest Cost 103 92 92 2 7 7 Expected Return on Plan Assets (171 ) (176 ) (171 ) — — — Amortization of Net Loss 30 41 41 — — — Amortization of Prior Service Cost — — — (7 ) (2 ) — Total Income Included in Other Income - Net (38 ) (43 ) (38 ) (5 ) 5 7 Net Periodic Benefit (Credit) Expense $ (7 ) $ (11 ) $ (2 ) $ (4 ) $ 7 $ 9 Restructuring Charge - Non Operating (a) — — 60 — — 13 Settlement (Gain) Loss — (1 ) 11 — — — Total (Credit) Expense $ (7 ) $ (12 ) $ 69 $ (4 ) $ 7 $ 22 (a) Charges related to special termination benefits and curtailment costs were the result of the management workforce reductions in first quarter 2017. See Restructuring Charge in Note 1, Nature of Operations and Significant Accounting Policies. As a result of the management workforce reduction programs initiated in 2017, $85 million in charges were incurred related to special termination benefits, curtailment and settlement changes. In 2017, the Company recorded special termination pension benefits of $56 million and remeasured the pension and other post-retirement benefits assets and obligations and recorded a curtailment loss of $4 million and $13 million , respectively, in restructuring charge - non-operating on the income statement. Pension settlement (gains) losses were recognized as a result of lump-sum payments to retirees exceeding the sum of the plan’s service and interest cost. The Company recorded an $11 million net settlement loss in 2017, of which a $12 million loss resulted from the retirements of former executives and is reported in restructuring charge - non-operating on the income statement. The other settlement gains in 2018 and 2017 were from one of the Company’s qualified pension plans with insignificant balances and were recorded in other income - net on the income statement. NOTE 9. Employee Benefit Plans, continued Pension and Other Post-retirement Benefits Adjustments The following table shows the pre-tax change in other comprehensive loss (income) attributable to certain components of net benefit expense and the change in benefit obligation for CSX for pension and other post-employment benefits. (Dollars in Millions) Pension Benefits Post-retirement Benefits Components of Other Comprehensive December December December December Loss (Income) 2019 2018 2019 2018 Recognized in the Balance Sheet Losses (Gains) $ 21 $ 223 $ 22 $ (112 ) Expense (Income) Recognized in the Income Statement Amortization of Net Losses (a) $ 30 $ 41 $ — $ — Settlement (Gain) Loss — (1 ) — — Amortization of Prior Service Costs — — (7 ) (2 ) (a) Amortization of net losses estimated to be expensed for 2020 is approximately $57 million for pension benefits. As of December 2019 , the balances to be amortized related to the Company's pension obligations is a pre-tax loss of $879 million and related to post-retirement obligations is a pre-tax gain of $74 million . These amounts are included in accumulated other comprehensive loss, a component of shareholders’ equity. Assumptions The expected long-term average rate of return on plan assets reflects the average rate of earnings expected on the funds invested, or to be invested, to provide for benefits included in the projected benefit obligation. In estimating that rate, the Company gives appropriate consideration to the returns being earned by the plan assets in the funds and the rates of return expected to be available for reinvestment as well as the current and projected asset mix of the funds. Management balances market expectations obtained from various investment managers and economists with both market and actual plan historical returns to develop a reasonable estimate of the expected long-term rate of return on assets. This assumption is reviewed annually and adjusted as deemed appropriate. The Company measures the service cost and interest cost components of the net pension and post-retirement benefits expense by using individual spot rates matched with separate cash flows for each future year. NOTE 9. Employee Benefit Plans, continued The weighted averages of assumptions used by the Company to value its pension and post-retirement obligations were as follows: Pension Benefits Post-retirement Benefits 2019 2018 2019 2018 Expected Long-term Return on Plan Assets: Benefit Cost for Current Plan Year 6.75 % 6.75 % N/A N/A Benefit Cost for Subsequent Plan Year 6.75 % 6.75 % N/A N/A Discount Rates: Benefit Cost for Plan Year Service Cost for Plan Year 4.40 % 3.74 % 4.14 % 4.14 % (a) Interest Cost for Plan Year 3.87 % 3.15 % 3.51 % 3.45 % (a) Benefit Obligation at End of Plan Year 3.13 % 4.24 % 2.87 % 3.98 % Salary Scale Inflation 4.60 % 4.60 % N/A N/A (a) The post-retirement benefits service cost and interest cost for 2018 were based on a weighted average discount rate of 3.68% and 2.79% , respectively, prior to the post-retirement plan amendments approved in 2018 and were increased to 4.14% and 3.45% , respectively, after the Company remeasured the other post-retirement benefits obligation in the fourth quarter of 2018. The impact of the health care cost trend rate is immaterial to the post-retirement benefit cost and obligation due to the plan's health reimbursement arrangement that covers Medicare-eligible retirees. Other Plans Under collective bargaining agreements, the Company participates in a multi-employer benefit plan, which provides certain post-retirement health care and life insurance benefits to eligible contract employees. Premiums under this plan are expensed as incurred and amounted to $26 million , $30 million and $40 million in 2019 , 2018 and 2017 , respectively. The Company maintains savings plans for virtually all full-time salaried employees and certain employees covered by collective bargaining agreements. Expense associated with these plans was $41 million , $41 million and $39 million for 2019 , 2018 and 2017 , respectively, and is included in labor and fringe expense on the consolidated income statement.

Debt and Credit Agreements

Debt and Credit Agreements	12 Months Ended
Debt and Credit Agreements	Dec. 31, 2019
Debt Disclosure [Abstract]
Debt and Credit Agreements	Debt and Credit Agreements Debt at December 2019 and December 2018 is shown in the table below. For information regarding the fair value of debt, see Note 13, Fair Value Measurements. Maturity at December Average Interest Rates at December December December (Dollars in Millions) 2019 2019 2019 2018 Notes 2020-2068 4.4% $ 16,056 $ 14,558 Equipment Obligations (a) 2020-2023 6.3% 178 195 Finance Leases 2020-2026 15.0% 4 4 Subtotal Long-term Debt (including current portion) $ 16,238 $ 14,757 Less Debt Due within One Year (245 ) (18 ) Long-term Debt (excluding current portion) $ 15,993 $ 14,739 (a) Equipment obligations are secured by an interest in certain railroad equipment. Debt Issuance & Early Redemption of Long-term Debt CSX issued the following notes which are included in the consolidated balance sheets under long-term debt and may be redeemed by the Company at any time, subject to payment of certain make-whole premiums: • On September 12, 2019, issued $400 million of 2.40% notes due 2030 and $600 million of 3.35% notes due 2049. On October 15, 2019, a portion of the net proceeds was used to fully redeem CSX’s outstanding $500 million of 3.70% notes that otherwise would have matured on October 30, 2020. • On February 28, 2019, issued $600 million of 4.25% notes due 2029, which was a reopening of existing notes originally issued in November 2018, and $400 million of 4.50% notes due 2049. • On November 15, 2018, issued $350 million of 4.25% notes due 2029 and $650 million of 4.75% notes due 2048. • On February 20, 2018, issued $800 million of 3.80% notes due 2028, $850 million of 4.30% notes due 2048, and $350 million of 4.65% notes due 2068. The net proceeds from debt issuances were used for general corporate purposes, which may include repurchases of CSX's common stock, capital investment, working capital requirements, improvements in productivity and other cost reductions at the Company’s major transportation units. NOTE 10. Debt and Credit Agreements, continued Long-term Debt Maturities (Net of Discounts, Premiums and Issuance Costs) (Dollars in Millions) Maturities at Fiscal Years Ending December 2019 2020 $ 245 2021 401 2022 162 2023 639 2024 551 Thereafter 14,240 Total Long-term Debt Maturities, including current portion $ 16,238 Credit Facilities In March 2019, CSX replaced its existing $1.0 billion unsecured, revolving credit facility with a new $1.2 billion unsecured, revolving credit facility backed by a diverse syndicate of banks. The new facility allows same-day borrowings at floating interest rates, based on LIBOR or an agreed-upon replacement, plus a spread that depends upon CSX's senior unsecured debt ratings. LIBOR is the London Interbank Offered Rate which is a daily reference rate based on the interest rates at which banks offer to lend unsecured funds. This facility expires in March 2024, and as of December 31, 2019, the Company had no outstanding balances under this facility. Commitment fees and interest rates payable under the facility were similar to fees and rates available to comparably rated investment-grade borrowers. As of December 31, 2019, CSX was in compliance with all covenant requirements under the facility. Commercial Paper Under its commercial paper program, which is backed by the revolving credit facility, the Company may issue unsecured commercial paper notes up to a maximum aggregate principal amount of $1.0 billion . Proceeds from issuances of the notes are expected to be used for general corporate purposes. At December 31, 2019, the Company had no

Revenues

Revenues	12 Months Ended
Revenues	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Revenues	Revenues The Company’s revenues are primarily derived from the transportation of freight as performance obligations that arise from its contracts with customers are satisfied. The following table presents the Company’s revenues disaggregated by market as this best depicts how the nature, amount, timing and uncertainty of revenue and cash flows are affected by economic factors. Fiscal Years (Dollars in millions) 2019 2018 2017 Chemicals $ 2,343 $ 2,339 $ 2,210 Agricultural and Food Products 1,410 1,306 1,262 Automotive 1,236 1,267 1,195 Forest Products 878 850 755 Metals and Equipment 741 769 703 Minerals 550 518 477 Fertilizers 431 442 466 Total Merchandise 7,589 7,491 7,068 Coal 2,070 2,246 2,107 Intermodal 1,760 1,931 1,799 Other 518 582 434 Total $ 11,937 $ 12,250 $ 11,408 Revenue Recognition The Company generates revenue from freight billings under contracts with customers generally on a rate per carload, container or ton-basis based on length of haul and commodities carried. The Company’s performance obligation arises when it receives a bill of lading (“BOL”) to transport a customer's commodities at a negotiated price contained in a transportation services agreement or a publicly disclosed tariff rate. Once a BOL is received, a contract is formed whereby the parties are committed to perform, collectability of consideration is probable and the rights of the parties, shipping terms and conditions, and payment terms are identified. A customer may submit several BOLs for transportation services at various times throughout a service agreement term but each shipment represents a distinct service that is a separately identified performance obligation. The average transit time to complete a shipment is between 3 to 8 days depending on market. Payments for transportation services are normally billed once a BOL is received and are generally due within 15 days after the invoice date. The Company recognizes revenue over transit time of freight as it moves from origin to destination. Revenue for services started but not completed at the reporting date is allocated based on the relative transit time in each reporting period, with the portion allocated for services subsequent to the reporting date considered remaining performance obligations. NOTE 11. Revenues, continued The certain key estimates included in the recognition and measurement of revenue and related accounts receivable are as follows: • Revenue associated with shipments in transit is recognized ratably over transit time and is based on average cycle times to move commodities and products from their origin to their final destination or interchange; • Adjustments to revenue for billing corrections and billing discounts; • Adjustments to revenue for overcharge claims filed by customers, which are based on historical payments to customers for rate overcharges as a percentage of total billing; and • Incentive-based refunds to customers, which are primarily volume-related, are recorded as a reduction to revenue on the basis of the projected liability (this estimate is based on historical activity, current volume levels and forecasted future volume). Revenue related to interline transportation services that involve the services of another party, such as another railroad, is reported on a net basis. The portion of the gross amount billed to customers that is remitted by the Company to another party is not reflected as revenue. Other revenue is comprised of revenue from regional subsidiary railroads and incidental charges , including demurrage and switching. It is recorded upon completion of the service and accounts for an immaterial percentage of the Company’s total revenue. Revenue from regional subsidiary railroads includes shipments by railroads that the Company does not directly operate. Demurrage represents charges assessed when freight cars are held by a customer beyond a specified period of time. Switching represents charges assessed when a railroad switches cars for a customer or another railroad. During 2019 , 2018 and 2017 , revenue recognized from performance obligations related to prior periods (for example, due to changes in transaction price), was not material. Remaining Performance Obligations Remaining performance obligations represent the transaction price allocated to future reporting periods for freight services started but not completed at the reporting date . This includes the unearned portion of billed and unbilled amounts for cancellable freight shipments in transit. The Company expects to recognize the unearned portion of revenue for freight services in transit within one week of the reporting date. As of December 31, 2019 , remaining performance obligations were not material. Contract Balances and Accounts Receivable The timing of revenue recognition, billings and cash collections results in accounts receivable and customer advances and deposits (contract liabilities) on the consolidated balance sheets. Contract assets, contract liabilities and deferred contract costs recorded on the consolidated balance sheet as of December 31, 2019 were not material. NOTE 11. Revenues, continued The Company’s accounts receivable - net consists of freight and non-freight receivables, reduced by an allowance for doubtful accounts. (Dollars in millions) December 31, December 31, Freight Receivables $ 790 $ 846 Freight Allowance for Doubtful Accounts (21 ) (18 ) Freight Receivables, net 769 828 Non-Freight Receivables 226 190 Non-Freight Allowance for Doubtful Accounts (9 ) (8 ) Non-Freight Receivables, net 217 182 Total Accounts Receivable, net $ 986 $ 1,010 Freight receivables include amounts earned, billed and unbilled , and currently due from customers for transportation-related services. Non-freight receivables include amounts billed and unbilled and currently due related to government reimbursement receivables and other non-revenue receivables. The Company maintains an allowance for doubtful accounts to provide for the estimated amount of receivables that will not be collected. The allowance is based upon an assessment of customer creditworthiness, historical payment experience, the age of outstanding receivables and economic conditions. Impairment losses recognized on the Company’s accounts receivable were not material in 2019 and 2018 .

Income Taxes

Income Taxes	12 Months Ended
Income Taxes	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Earnings before income taxes of $4.3 billion , $4.3 billion and $3.1 billion for fiscal years 2019 , 2018 and 2017 , respectively, represent earnings from domestic operations. The breakdown of income tax expense between current and deferred is as follows: Fiscal Years (Dollars in Millions) 2019 2018 2017 Current: Federal $ 608 $ 572 $ 787 State 104 144 117 Subtotal Current 712 716 904 Deferred: Federal 235 275 (3,277 ) State 38 4 44 Subtotal Deferred 273 279 (3,233 ) Total $ 985 $ 995 $ (2,329 ) NOTE 12. Income Taxes, continued The Company recorded a 2019 income tax benefit of $77 million primarily as a result of the additional tax benefit associated with vesting of share-based awards, the settlement of certain state tax matters, federal and state legislative change, and a change in the valuation of deferred taxes as a result of filing the 2018 tax returns. The Company recorded a 2018 income tax benefit of $62 million primarily as a result of the additional tax benefit associated with vesting of share-based awards, state legislative changes, the settlement of certain state tax matters and a change in the valuation of deferred taxes as a result of filing the 2017 tax returns. With the enactment of the Tax Cuts and Jobs Act (the "Act" or "tax reform") on December 22, 2017, the Company's 2017 financial results included a $3.5 billion , or $3.81 per share, non-cash reduction in income tax expense, primarily resulting from revaluing the Company's net deferred tax liabilities to reflect the enacted 21% federal corporate tax rate effective January 1, 2018. During third quarter 2018, the Company filed its 2017 Federal Income Tax return which resulted in an immaterial adjustment to the deferred tax liability and tax expense. Accordingly, the Company's accounting for the federal rate reduction under the the Act is now complete. The Company's affiliates also revalued their deferred tax liabilities to reflect the lower federal corporate tax rate, which resulted in the Company recognizing a benefit in 2017 of $142 million , or $0.10 per share after-tax, in equity earnings of affiliates, which is included in operating income. (See additional discussion over equity earnings of affiliates in Note 15, Related Parties and Affiliates .) In addition to the tax benefit related to tax reform, the Company recorded a 2017 income tax benefit of $21 million primarily as a result of the additional tax benefit associated with vesting of share-based awards, state legislative changes, a change in the apportionment of state taxable income and the related impact on the valuation of deferred taxes and the settlement of certain state tax matters . Income tax expense reconciled to the tax computed at statutory rates is presented in the following table. Fiscal Years (Dollars In Millions) 2019 2018 2017 Federal Income Taxes $ 906 21.0 % $ 904 21.0 % $ 1,100 35.0 % State Income Taxes 108 2.5 % 112 2.6 % 102 3.2 % Deferred Tax Rate Change — — % — — % (3,506 ) (111.6 )% Other (29 ) (0.7 )% (21 ) (0.5 )% (25 ) (0.8 )% Income Tax (Benefit) Expense/Rate $ 985 22.8 % $ 995 23.1 % $ (2,329 ) (74.2 )% NOTE 12. Income Taxes, continued The primary factors in the change in year-end net deferred income tax liability balances include the annual provision for deferred income tax expense and accumulated other comprehensive income/loss. The significant components of deferred income tax assets and liabilities include: 2019 2018 (Dollars in Millions) Assets Liabilities Assets Liabilities Pension Plans $ 71 $ — $ 79 $ — Other Employee Benefit Plans 127 — 146 — Accelerated Depreciation — 7,020 — 6,799 Other 426 565 529 645 Total $ 624 $ 7,585 $ 754 $ 7,444 Net Deferred Income Tax Liabilities $ 6,961 $ 6,690 The Company files a consolidated federal income tax return, which includes its principal domestic subsidiaries. CSX and its subsidiaries are subject to U.S. federal income tax as well as income tax of multiple state jurisdictions. CSX participated in a contemporaneous IRS audit of tax years 2019 and 2018. Federal examinations of original federal income tax returns for all years through 2017 are resolved. As of December 2019 , 2018 and 2017 , the Company had approximately $13 million , $12 million and $24 million , respectively, of total unrecognized tax benefits as a result of uncertain tax positions. Net tax benefits of $10 million , $9 million and $19 million in 2019 , 2018 and 2017 , respectively, could favorably impact the effective income tax rate in each year. The Company does not expect that unrecognized tax benefits as of December 2019 for various state and federal income tax matters will significantly change over the next 12 months. The final outcome of these uncertain tax positions is not yet determinable. There were no material changes to the total gross unrecognized tax benefits and prior year audit resolutions of the Company during the fiscal year ended December 2019 . CSX’s continuing practice is to recognize net interest and penalties related to income tax matters in income tax expense. Included in the consolidated income statements is expense of $1 million in 2019 , a benefit of $3 million in 2018 , and expense of $3 million in 2017 for changes to reserves for interest and penalties for all prior year tax positions. The Company had $2 million , $2 million and $6 million accrued for interest and penalties at 2019 , 2018 and 2017 , respectively, for all prior year tax positions.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
Fair Value Measurements	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The Financial Instruments Topic in the ASC requires disclosures about fair value of financial instruments in annual reports as well as in quarterly reports. For CSX, this statement applies to certain investments, pension plan assets and long-term debt. Also, the Fair Value Measurements and Disclosures Topic in the ASC clarifies the definition of fair value for financial reporting, establishes a framework for measuring fair value and requires additional disclosures about the use of fair value measurements. Various inputs are considered when determining the value of the Company's investments, pension plan assets and long-term debt. The inputs or methodologies used for valuing securities are not necessarily an indication of the risk associated with investing in these securities. These inputs are summarized in the three broad levels listed below: • Level 1 – observable market inputs that are unadjusted quoted prices for identical assets or liabilities in active markets; • Level 2 – other significant observable inputs (including quoted prices for similar securities, interest rates, credit risk, etc.); and • Level 3 – significant unobservable inputs (including the Company’s own assumptions about the assumptions market participants would use in determining the fair value of investments). The valuation methods described below may produce a fair value calculation that may not be indicative of net realizable value or reflective of future fair values. Furthermore, while the Company believes its valuation methods are appropriate and consistent with other market participants, the use of different methodologies or assumptions to determine the fair value of certain financial instruments could result in a different fair value measurement at the reporting date. Investments The Company's investment assets, valued with assistance from a third-party trustee, consist of certificates of deposits, commercial paper, corporate bonds and government securities and are carried at fair value on the consolidated balance sheet per the Fair Value Measurements and Disclosures Topic in the ASC. There are several valuation methodologies used for those assets as described below: • Certificates of Deposit and Commercial Paper (Level 2): Valued at amortized cost, which approximates fair value; and • Corporate Bonds and Government Securities (Level 2): Valued using broker quotes that utilize observable market inputs. NOTE 13. Fair Value Measurements, continued The Company's investment assets are carried at fair value on the consolidated balance sheets as summarized in the following table. All of the inputs used to determine the fair value of the Company's investments are Level 2 inputs. The amortized cost basis of these investments was $1.1 billion and $340 million as of December 31, 2019 and December 31, 2018 , respectively. Fiscal Years 2019 2018 (Dollars in Millions) Level 2 Level 2 Certificates of Deposit and Commercial Paper $ 989 $ 250 Corporate Bonds 59 56 Government Securities 36 35 Total investments at fair value $ 1,084 $ 341 These investments have the following maturities and are represented on the consolidated balance sheet within short-term investments for investments with maturities of less than one year, and other long-term assets for investments with maturities of one year and greater: (Dollars in Millions) December 2019 December 2018 Less than 1 year $ 996 $ 253 1 - 5 years 10 14 5 - 10 years 25 26 Greater than 10 years 53 48 Total investments at fair value $ 1,084 $ 341 Long-term Debt Long-term debt is reported at carrying amount on the consolidated balance sheets and is the Company's only financial instrument with fair values significantly different from their carrying amounts. The majority of the Company's long-term debt is valued with assistance from a third party that utilizes closing transactions, market quotes or market values of comparable debt. For those instruments not valued by the third party, the fair value has been estimated by applying market rates of similar instruments to the scheduled contractual debt payments and maturities. These market rates are provided by the same third party. All of the inputs used to determine the fair value of the Company's long-term debt are Level 2 inputs. The fair value of outstanding debt fluctuates with changes in a number of factors. Such factors include, but are not limited to, interest rates, market conditions, credit ratings, values of similar financial instruments, size of the transaction, cash flow projections and comparable trades. Fair value will exceed carrying value when the current market interest rate is lower than the interest rate at which the debt was originally issued. The fair value of a company's debt is a measure of its current value under present market conditions. It does not impact the financial statements under current accounting rules. NOTE 13. Fair Value Measurements, continued The fair value and carrying value of the Company's long-term debt is as follows: (Dollars in Millions) December 2019 December 2018 Long-term Debt (Including Current Maturities): Fair Value $ 18,503 $ 14,914 Carrying Value 16,238 14,757 Pension Plan Assets Pension plan assets are reported at fair value, net of pension liabilities, on the consolidated balance sheet. The Investment Committee targets an allocation of pension assets to be generally 60% equity and 40% fixed income. There are several valuation methodologies used for those assets as described below. Investments in the Fair Value Hierarchy • Common stock (Level 1): Valued at the closing price reported on the active market on which the individual securities are traded on the last day of the year and classified in Level 1 of the fair value hierarchy. • Mutual funds (Level 1 ): Valued at the net asset value of shares held at year end based on quoted market prices determined in an active market. These assets are classified in Level 1 of the fair value hierarchy. • Cash and cash equivalents (Level 1) : Includes cash and short term investments with an original maturity of three months or less. The carrying value of cash and cash equivalents at year end approximates fair value. These assets are classified in Level 1 of the fair value hierarchy. • Corporate bonds, government securities, asset-backed securities and derivatives (Level 2) : Valued using price evaluations reflecting the bid and/or ask sides of the market for a similar investment at year end. Asset-backed securities include commercial mortgage-backed securities and collateralized mortgage obligations. These assets are classified in Level 2 of the fair value hierarchy. Investments Measured at Net Asset Value • Partnerships: Net asset value of private equity is based on the fair market values associated with the underlying investments at year end. These funds have redemption restrictions that require advanced notice of 15 business days. • Common collective trust funds: This class consists of private funds that invest in government and corporate securities and various short-term debt instruments and are measured at net asset value to estimate the fair value of the investments. The net asset value of the investments is determined by reference to the fair value of the underlying securities, which are valued primarily through the use of directly or indirectly observable inputs. These funds have redemption restrictions that require advanced notice of up to 15 business days. NOTE 13. Fair Value Measurements, continued The pension plan assets at fair value by level, within the fair value hierarchy, as of calendar plan years 2019 and 2018 are shown in the table below. For additional information related to pension assets, see Note 9, Employee Benefit Plans. Fiscal Years 2019 2018 (Dollars in Millions) Level 1 Level 2 Total Level 1 Level 2 Total Common Stock $ 823 $ — $ 823 $ 750 $ — $ 750 Mutual funds 78 — 78 7 — 7 Cash and cash equivalents 229 — 229 3 — 3 Corporate bonds — 588 588 — 537 537 Government securities — 217 217 — 149 149 Asset-backed securities — 8 8 — 10 10 Derivatives and other — 9 9 — 5 5 Total investments in the fair value hierarchy $ 1,130 $ 822 $ 1,952 $ 760 $ 701 $ 1,461 Investments measured at net asset value (a) n/a n/a $ 873 n/a n/a $ 970 Investments at fair value $ 1,130 $ 822 $ 2,825 $ 760 $ 701 $ 2,431

Other Income - Net

Other Income - Net	12 Months Ended
Other Income - Net	Dec. 31, 2019
Other Income and Expenses [Abstract]
Other Income - Net	Other Income - Net The Company derives income from items that are not considered operating activities. Income from these items is reported net of related expense. All components of net periodic pension and post-retirement benefit costs, excluding service cost, are included in other income - net on the consolidated income statement. Miscellaneous income (expense) may fluctuate due to timing and includes investment gains, losses and interest income as well as other non-operating activities. Interest income increased from 2018 to 2019, and from 2017 to 2018, primarily as a result of higher average investment balances. Miscellaneous expense in 2019 includes $10 million of costs associated with the early redemption of long-term debt. Other income – net consisted of the following: Fiscal Years (Dollars in Millions) 2019 2018 2017 Net Periodic Pension and Post-retirement Benefit Credit (a) $ 43 $ 38 $ 32 Interest Income 48 32 13 Miscellaneous (Expense) Income (3 ) 4 8 Total Other Income - Net $ 88 $ 74 $ 53

Related Parties and Affiliates

Related Parties and Affiliates	12 Months Ended
Related Parties and Affiliates	Dec. 31, 2019
Related Party Transactions [Abstract]
Related Parties and Affiliates	Related Parties and Affiliates Conrail Through a limited liability company, CSX and Norfolk Southern Corporation (“NS”) jointly own Conrail. CSX has a 42% economic interest and 50% voting interest in the jointly-owned entity, and NS has the remainder of the economic and voting interests. CSX's investment of $982 million is included on the consolidated balance sheet as investment in Conrail. Pursuant to the Investments-Equity Method and Joint Venture Topic in the ASC, CSX applies the equity method of accounting to its investment in Conrail. Conrail owns rail infrastructure and operates for the joint benefit of CSX and NS. This is known as the shared asset area. Conrail charges fees for right-of-way usage, equipment rentals and transportation, switching and terminal service charges in the shared asset area. These expenses are included in materials, supplies and other on the consolidated income statements. Future payments due to Conrail under the shared asset area agreements are shown in the table below. (Dollars in Millions) Conrail Shared Years Asset Agreement 2020 $ 29 2021 29 2022 29 2023 29 2024 22 Thereafter — Total $ 138 Also, included in equity earnings of affiliates are CSX’s 42 percent share of Conrail’s income and its amortization of the fair value write-up arising from the acquisition of Conrail and certain other adjustments. The amortization primarily represents the additional after-tax depreciation expense related to the write-up of Conrail’s fixed assets when the original purchase price, from the 1997 acquisition of Conrail, was allocated based on fair value. This write-up of fixed assets resulted in a difference between CSX's investment in Conrail and its share of Conrail's underlying net equity, which is $339 million as of December 2019 . NOTE 15. Related Parties and Affiliates, continued The following table discloses amounts related to Conrail. Purchase price amortization and equity earnings are included in equity earnings of affiliates and all other amounts in the table are included in materials, supplies and other expenses on the Company’s consolidated income statements. Fiscal Years (Dollars in Millions) 2019 2018 2017 Rents, fees and services $ 119 $ 117 $ 120 Purchase price amortization and other 4 4 4 Equity earnings of Conrail (42 ) (43 ) (58 ) Total Conrail Expense $ 81 $ 78 $ 66 As required by the Related Party Disclosures Topic in the ASC, the Company has identified amounts below owed to Conrail, or its subsidiaries, representing liabilities under the operating, equipment and shared area agreements with Conrail. In 2014, the Company executed two promissory notes with a subsidiary of Conrail which were included in long-term debt on the consolidated balance sheets. Interest expense from these promissory notes was $6 million in each 2019 , 2018 and 2017 . December December (Dollars in Millions) 2019 2018 Balance Sheet Information: CSX accounts payable to Conrail $ 213 $ 153 Promissory notes payable to Conrail subsidiary 2.89% CSX promissory note due October 2044 73 73 2.89% CSXT promissory note due October 2044 151 151 TTX Company TTX Company ("TTX") is a privately-held corporation engaged in the business of providing its owner-railroads with standardized fleets of intermodal, automotive and general use railcars at time and mileage rates. CSX owns about 20 percent of TTX's common stock, and the remaining is owned by the other leading North American railroads and their affiliates. CSX's investment in TTX is $743 million and is included in affiliates and other companies in the consolidated balance sheet. Pursuant to the Investments-Equity Method topic in the ASC, CSX applies the equity method of accounting to its investment in TTX. NOTE 15. Related Parties and Affiliates, continued As required by the Related Party Disclosures Topic in the ASC, the following table discloses amounts related to TTX. Car hire rents are included in equipment and other rents expense and equity earnings are included in equity earnings of affiliates in the Company’s consolidated income statements. Also included below is balance sheet information related to CSX's payable to TTX, which represents car rental liabilities. Fiscal Years (Dollars in Millions) 2019 2018 2017 Income statement information: Car hire rents $ 223 $ 223 $ 237 Equity earnings of TTX (56 ) (60 ) (157 ) Total TTX expense $ 167 $ 163 $ 80 December December Balance sheet information: 2019 2018 CSX payable to TTX $ 34 $ 36 Tax Reform Effect on Equity Earnings of Affiliates Due to the enactment of tax reform, the Company recognized a benefit in 2017 of $142 million , or $0.10 per share after-tax, in its equity earnings of affiliates. This benefit was primarily the result of the Company's affiliates (primarily TTX and Conrail) revaluing their deferred tax liabilities to reflect the lower federal corporate tax rate, which favorably impacted their net earnings for 2017. See additional discussion of tax reform in Note 12, Income Taxes. Other Related Party Transactions On October 17, 2019, the Company repurchased 4.7 million shares for $319 million from MR Argent Advisor LLC, a CSX shareholder. See additional discussion in Note 2, Earnings Per Share.

Other Comprehensive Income _ (L

Other Comprehensive Income / (Loss)	12 Months Ended
Other Comprehensive Income / (Loss)	Dec. 31, 2019
Equity [Abstract]
Other Comprehensive Income / (Loss)	Other Comprehensive Income / (Loss) CSX reports comprehensive earnings or loss in accordance with the Comprehensive Income Topic in the ASC in the consolidated comprehensive income statement. Total comprehensive earnings are defined as all changes in shareholders' equity during a period, other than those resulting from investments by and distributions to shareholders (e.g. issuance of equity securities and dividends). Generally, for CSX, total comprehensive earnings equal net earnings plus or minus adjustments for pension and other post-retirement liabilities. Total comprehensive earnings represent the activity for a period net of tax and were $3.3 billion , $3.1 billion and $5.6 billion for 2019 , 2018 and 2017 , respectively. NOTE 16. Other Comprehensive Income / (Loss), continued While total comprehensive earnings is the activity in a period and is largely driven by net earnings in that period, accumulated other comprehensive income or loss (“AOCI”) represents the cumulative balance of other comprehensive income, net of tax, as of the balance sheet date. For CSX, AOCI is primarily the cumulative balance related to pension and other post-retirement benefit adjustments and CSX's share of AOCI of equity method investees. Changes in the AOCI balance by component are shown in the following table. Amounts reclassified in pension and other post-employment benefits to net earnings relate to the amortization of actuarial losses and are included in other income-net on the consolidated income statements. See Note 9. Employee Benefit Plans for further information. Other primarily represents CSX's share of AOCI of equity method investees. Amounts reclassified in other to net earnings are included in equity earnings of affiliates on the consolidated income statements. Pension and Other Post-Employment Benefits Other Accumulated Other Comprehensive Income (Loss) (Dollars in millions) Balance December 30, 2016 - Net of Tax $ (580 ) $ (60 ) $ (640 ) Other Comprehensive Income (Loss) Income Before Reclassifications 148 13 161 Amounts Reclassified to Net Earnings 56 2 58 Tax Expense (64 ) (1 ) (65 ) Total Other Comprehensive Income 140 14 154 Balance December 31, 2017 - Net of Tax (440 ) (46 ) (486 ) Other Comprehensive Income (Loss) Reclassification of Stranded Tax Effects (a) (108 ) 1 (107 ) Loss Before Reclassifications (111 ) (8 ) (119 ) Amounts Reclassified to Net Earnings 38 (6 ) 32 Tax Benefit 17 2 19 Total Other Comprehensive Loss (164 ) (11 ) (175 ) Balance December 31, 2018 - Net of Tax (604 ) (57 ) (661 ) Other Comprehensive Income (Loss) Loss Before Reclassifications (43 ) (5 ) (48 ) Amounts Reclassified to Net Earnings 23 8 31 Tax Benefit 5 (2 ) 3 Total Other Comprehensive (Loss) Income (15 ) 1 (14 ) Balance December 31, 2019 - Net of Tax $ (619 ) $ (56 ) $ (675 )

Quarterly Financial Data (Unaud

Quarterly Financial Data (Unaudited)	12 Months Ended
Quarterly Financial Data (Unaudited)	Dec. 31, 2019
Quarterly Financial Information Disclosure [Abstract]
Quarterly Financial Data (Unaudited)	Quarterly Financial Data (Unaudited) Pursuant to Article 3 of the SEC’s Regulation S-X, the following are selected quarterly financial data: Fiscal Year Ended December 2019 Quarters (Dollars in Millions, Except Per Share Amounts) 1st 2nd 3rd 4th Full Year Revenue $ 3,013 $ 3,061 $ 2,978 $ 2,885 $ 11,937 Operating Income 1,219 1,305 1,287 1,154 4,965 Net Earnings 834 870 856 771 3,331 Earnings Per Share, Basic $ 1.02 $ 1.08 $ 1.08 $ 0.99 $ 4.18 Earnings Per Share, Assuming Dilution 1.02 1.08 1.08 0.99 4.17 Fiscal Year Ended December 2018 Revenue $ 2,876 $ 3,102 $ 3,129 $ 3,143 $ 12,250 Operating Income 1,044 1,283 1,293 1,249 4,869 Net Earnings 695 877 894 843 3,309 Earnings Per Share, Basic $ 0.78 $ 1.02 $ 1.05 $ 1.02 $ 3.86 Earnings Per Share, Assuming Dilution 0.78 1.01 1.05 1.01 3.84

Summarized Consolidating Financ

Summarized Consolidating Financial Data	12 Months Ended
Summarized Consolidating Financial Data	Dec. 31, 2019
Condensed Financial Information Disclosure [Abstract]
Summarized Consolidating Financial Data	Summarized Consolidating Financial Data In 2007, CSXT, a wholly-owned subsidiary of CSX Corporation, sold secured equipment notes maturing in 2023 in a registered public offering. CSX has fully and unconditionally guaranteed the notes. In connection with the notes, the Company is providing the following condensed consolidating financial information in accordance with SEC disclosure requirements. Each entity in the consolidating financial information follows the same accounting policies as described in the consolidated financial statements, except for the use of the equity method of accounting to reflect ownership interests in subsidiaries which are eliminated upon consolidation and the allocation of certain expenses of CSX incurred for the benefit of its subsidiaries. Condensed consolidating financial information for the obligor, CSXT, and parent guarantor, CSX, is shown in the following tables. NOTE 18. Summarized Consolidating Financial Data, continued Consolidating Income Statements (Dollars in Millions) Fiscal Year Ended December 2019 CSX Corporation CSX Transportation Eliminations and Other CSX Consolidated Revenue $ — $ 11,856 $ 81 $ 11,937 Expense (549 ) 7,688 (167 ) 6,972 Operating Income 549 4,168 248 4,965 Equity in Earnings of Subsidiaries 3,505 — (3,505 ) — Interest Expense (878 ) (42 ) 183 (737 ) Other Income - Net 25 207 (144 ) 88 Earnings Before Income Taxes 3,201 4,333 (3,218 ) 4,316 Income Tax Benefit (Expense) 130 (1,009 ) (106 ) (985 ) Net Earnings $ 3,331 $ 3,324 $ (3,324 ) $ 3,331 Total Comprehensive Earnings $ 3,317 $ 3,306 $ (3,306 ) $ 3,317 Fiscal Year Ended December 2018 Revenue $ — $ 12,174 $ 76 $ 12,250 Expense (344 ) 7,868 (143 ) 7,381 Operating Income 344 4,306 219 4,869 Equity in Earnings of Subsidiaries 3,580 — (3,580 ) — Interest Expense (742 ) (39 ) 142 (639 ) Other Income - Net 24 152 (102 ) 74 Earnings Before Income Taxes 3,206 4,419 (3,321 ) 4,304 Income Tax Benefit (Expense) 103 (1,036 ) (62 ) (995 ) Net Earnings $ 3,309 $ 3,383 $ (3,383 ) $ 3,309 Total Comprehensive Earnings $ 3,134 $ 3,441 $ (3,441 ) $ 3,134 Fiscal Year Ended December 2017 Revenue $ — $ 11,334 $ 74 $ 11,408 Expense (158 ) 8,009 (163 ) 7,688 Operating Income 158 3,325 237 3,720 Equity in Earnings of Subsidiaries 5,810 — (5,810 ) — Interest Expense (582 ) (29 ) 65 (546 ) Other Income - Net 7 (19 ) (20 ) (32 ) Earnings Before Income Taxes 5,393 3,277 (5,528 ) 3,142 Income Tax Benefit 78 2,247 4 2,329 Net Earnings $ 5,471 $ 5,524 $ (5,524 ) $ 5,471 Total Comprehensive Earnings $ 5,625 $ 5,538 $ (5,538 ) $ 5,625 NOTE 18. Summarized Consolidating Financial Data, continued Consolidating Balance Sheets (Dollars in Millions) As of December 31, 2019 CSX Corporation CSX Transportation Eliminations and Other CSX ASSETS Current Assets: Cash and Cash Equivalents $ 814 $ 136 $ 8 $ 958 Short-term Investments 989 — 7 996 Accounts Receivable - Net 4 969 13 986 Receivable from Affiliates 1,054 7,405 (8,459 ) — Materials and Supplies — 261 — 261 Other Current Assets 26 30 21 77 Total Current Assets 2,887 8,801 (8,410 ) 3,278 Properties 1 42,110 2,989 45,100 Accumulated Depreciation (1 ) (11,199 ) (1,732 ) (12,932 ) Properties - Net — 30,911 1,257 32,168 Investments in Conrail — — 982 982 Affiliates and Other Companies (39 ) 923 13 897 Investment in Consolidated Subsidiaries 34,528 — (34,528 ) — Right of Use Lease Asset — 514 18 532 Other Long-term Assets 3 629 (232 ) 400 Total Assets $ 37,379 $ 41,778 $ (40,900 ) $ 38,257 LIABILITIES AND SHAREHOLDERS' EQUITY Current Liabilities: Accounts Payable $ 153 $ 830 $ 60 $ 1,043 Labor and Fringe Benefits Payable 38 386 65 489 Payable to Affiliates 9,552 574 (10,126 ) — Casualty, Environmental and Other Reserves — 87 13 100 Current Maturities of Long-term Debt — 245 — 245 Income and Other Taxes Payable (286 ) 340 15 69 Other Current Liabilities — 192 13 205 Total Current Liabilities 9,457 2,654 (9,960 ) 2,151 Casualty, Environmental and Other Reserves — 169 36 205 Long-term Debt 15,534 459 — 15,993 Deferred Income Taxes - Net (152 ) 6,827 286 6,961 Long-term Lease Liability — 481 12 493 Other Long-term Liabilities 692 215 (316 ) 591 Total Liabilities 25,531 10,805 (9,942 ) 26,394 Shareholders' Equity: Common Stock, $1 Par Value 773 181 (181 ) 773 Other Capital 346 5,096 (5,096 ) 346 Retained Earnings 11,404 25,646 (25,646 ) 11,404 Accumulated Other Comprehensive Loss (675 ) 35 (35 ) (675 ) Noncontrolling Minority Interest — 15 — 15 Total Shareholders' Equity 11,848 30,973 (30,958 ) 11,863 Total Liabilities and Shareholders' Equity $ 37,379 $ 41,778 $ (40,900 ) $ 38,257 NOTE 18. Summarized Consolidating Financial Data, continued Consolidating Balance Sheets (Dollars in Millions) As of December 31, 2018 CSX Corporation CSX Transportation Eliminations and Other CSX ASSETS Current Assets Cash and Cash Equivalents $ 716 $ 130 $ 12 $ 858 Short-term Investments 250 — 3 253 Accounts Receivable - Net 1 1,003 6 1,010 Receivable from Affiliates 1,020 5,214 (6,234 ) — Materials and Supplies — 263 — 263 Other Current Assets 63 104 14 181 Total Current Assets 2,050 6,714 (6,199 ) 2,565 Properties 1 41,897 2,907 44,805 Accumulated Depreciation (1 ) (11,194 ) (1,612 ) (12,807 ) Properties - Net — 30,703 1,295 31,998 Investments in Conrail — — 943 943 Affiliates and Other Companies (39 ) 859 16 836 Investment in Consolidated Subsidiaries 32,033 — (32,033 ) — Other Long-term Assets 2 598 (213 ) 387 Total Assets $ 34,046 $ 38,874 $ (36,191 ) $ 36,729 LIABILITIES AND SHAREHOLDERS' EQUITY Current Liabilities Accounts Payable $ 132 $ 763 $ 54 $ 949 Labor and Fringe Benefits Payable 41 440 69 550 Payable to Affiliates 6,973 633 (7,606 ) — Casualty, Environmental and Other Reserves — 99 14 113 Current Maturities of Long-term Debt — 18 — 18 Income and Other Taxes Payable (290 ) 392 4 106 Other Current Liabilities 11 162 6 179 Total Current Liabilities 6,867 2,507 (7,459 ) 1,915 Casualty, Environmental and Other Reserves — 176 35 211 Long-term Debt 14,029 710 — 14,739 Deferred Income Taxes - Net (134 ) 6,601 223 6,690 Other Long-term Liabilities 721 211 (338 ) 594 Total Liabilities 21,483 10,205 (7,539 ) 24,149 Shareholders' Equity Common Stock, $1 Par Value 818 181 (181 ) 818 Other Capital 249 5,096 (5,096 ) 249 Retained Earnings 12,157 23,322 (23,322 ) 12,157 Accumulated Other Comprehensive Loss (661 ) 53 (53 ) (661 ) Noncontrolling Minority Interest — 17 — 17 Total Shareholders' Equity 12,563 28,669 (28,652 ) 12,580 Total Liabilities and Shareholders' Equity $ 34,046 $ 38,874 $ (36,191 ) $ 36,729 NOTE 18. Summarized Consolidating Financial Data, continued Consolidating Cash Flow Statements (Dollars in Millions) Fiscal Year Ended December 2019 CSX Corporation CSX Transportation Eliminations and Other CSX Operating Activities Net Cash Provided by (Used in) Operating Activities $ 3,440 $ 2,272 $ (862 ) $ 4,850 Investing Activities Property Additions — (1,506 ) (151 ) (1,657 ) Purchases of Short-term Investments (2,838 ) — — (2,838 ) Proceeds from Sales of Short-term Investments 2,105 — 3 2,108 Proceeds from Property Dispositions — 254 — 254 Other Investing Activities 15 10 6 31 Net Cash Used in Investing Activities (718 ) (1,242 ) (142 ) (2,102 ) Financing Activities Long-term Debt Issued 2,000 — — 2,000 Long-term Debt Repaid (500 ) (18 ) — (518 ) Dividends Paid (763 ) (1,000 ) 1,000 (763 ) Shares Repurchased (3,373 ) — — (3,373 ) Other Financing Activities 12 (6 ) — 6 Net Cash (Used in) Provided by Financing Activities (2,624 ) (1,024 ) 1,000 (2,648 ) Net Increase in Cash and Cash Equivalents 98 6 (4 ) 100 Cash and Cash Equivalents at Beginning of Period 716 130 12 858 Cash and Cash Equivalents at End of Period $ 814 $ 136 $ 8 $ 958 NOTE 18. Summarized Consolidating Financial Data, continued Consolidating Cash Flow Statements (Dollars in Millions) Fiscal Year Ended December 2018 CSX Corporation CSX Transportation Eliminations and Other CSX Operating Activities Net Cash Provided by (Used in) Operating Activities $ 3,182 $ 1,657 $ (198 ) $ 4,641 Investing Activities Property Additions — (1,580 ) (165 ) (1,745 ) Purchases of Short-term Investments (734 ) — (2 ) (736 ) Proceeds from Sales of Short-term Investments 485 — 20 505 Proceeds from Property Dispositions — 319 — 319 Other Investing Activities (4 ) 638 (661 ) (27 ) Net Cash Used in Investing Activities (253 ) (623 ) (808 ) (1,684 ) Financing Activities Long-term Debt Issued 3,000 — — 3,000 Long-term Debt Repaid — (19 ) — (19 ) Dividends Paid (751 ) (1,000 ) 1,000 (751 ) Shares Repurchased (4,671 ) — — (4,671 ) Other Financing Activities (65 ) (6 ) 12 (59 ) Net Cash (Used in) Provided by Financing Activities (2,487 ) (1,025 ) 1,012 (2,500 ) Net Decrease in Cash and Cash Equivalents 442 9 6 457 Cash and Cash Equivalents at Beginning of Period 274 121 6 401 Cash and Cash Equivalents at End of Period $ 716 $ 130 $ 12 $ 858 NOTE 18. Summarized Consolidating Financial Data, continued Consolidating Cash Flow Statements (Dollars in Millions) Fiscal Year Ended December 2017 CSX Corporation CSX Transportation Eliminations and Other CSX Operating Activities Net Cash Provided by (Used in) Operating Activities $ 1,719 $ 2,112 $ (359 ) $ 3,472 Investing Activities Property Additions — (1,848 ) (192 ) (2,040 ) Purchases of Short-term Investments (774 ) — (8 ) (782 ) Proceeds from Sales of Short-term Investments 1,190 — 3 1,193 Proceeds from Property Dispositions — 97 — 97 Other Investing Activities (2 ) 94 (55 ) 37 Net Cash Provided by (Used in) Investing Activities 414 (1,657 ) (252 ) (1,495 ) Financing Activities Long-term Debt Issued 850 — — 850 Long-term Debt Repaid (313 ) (20 ) — (333 ) Dividends Paid (708 ) (600 ) 600 (708 ) Shares Repurchased (1,970 ) — — (1,970 ) Other Financing Activities (23 ) 5 — (18 ) Net Cash (Used in) Provided by Financing Activities (2,164 ) (615 ) 600 (2,179 ) Net (Decrease) Increase in Cash and Cash Equivalents (31 ) (160 ) (11 ) (202 ) Cash and Cash Equivalents at Beginning of Period 305 281 17 603 Cash and Cash Equivalents at End of Period $ 274 $ 121 $ 6 $ 401

Nature of Operations and Sign_2

Nature of Operations and Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	In the opinion of management, the accompanying consolidated financial statements contain all normal, recurring adjustments necessary to fairly present the financial position of CSX and its subsidiaries at December 31, 2019 and December 31, 2018 , and the consolidated statements of income, comprehensive income, cash flows and changes in shareholders’ equity for fiscal years 2019 , 2018 and 2017 . Where applicable, prior year information has been reclassified to conform to current presentation. In addition, management has evaluated and disclosed all material events occurring subsequent to the date of the financial statements up to the date this annual report is filed on Form 10-K.
Fiscal Year	Through the second quarter 2017, CSX followed a 52/53 week fiscal reporting calendar with the last day of each reporting period ending on a Friday. On July 7, 2017, the Board of Directors of CSX approved a change in the fiscal reporting calendar from a 52/53 week year ending on the last Friday of December to a calendar year ending on December 31 each year, effective beginning with fiscal third quarter 2017. Related to the change in the fiscal calendar, 2019 and 2018 both contained 365 days while 2017 contained 366 days. This change did not materially impact comparability of the Company’s financial results for fiscal year 2017. Accordingly, the change to a calendar fiscal year was made on a prospective basis and operating results for prior periods were not adjusted. The Company was not required to file a transition report because this change was not deemed a change in fiscal year for purposes of reporting subject to Rule 13a-10 or Rule 15d-10 of the Securities Exchange Act of 1934 as the new fiscal year commenced with the end of the prior fiscal year end. Except as otherwise specified, references to full years indicate CSX’s fiscal years ended on December 31, 2019, December 31, 2018 and December 31, 2017.
Principles of Consolidation	The consolidated financial statements include results of operations of CSX and subsidiaries over which CSX has majority ownership or financial control. All significant intercompany accounts and transactions have been eliminated. Most investments in companies that were not majority-owned were carried at cost (if less than 20% owned and the Company has no significant influence) or were accounted for under the equity method (if the Company has significant influence but does not have control). These investments are reported within Investment in Conrail or Affiliates and Other Companies on the consolidated balance sheets.
Cash and Cash Equivalents	On a daily basis, cash in excess of current operating requirements is invested in various highly liquid investments having a typical maturity date of three
Investments	Investments in instruments with original maturities greater than three months that will mature in less than one year are classified as short-term investments. Investments with original maturities of one year or greater are initially classified within other long-term assets, and the classification is re-evaluated at each balance sheet date.
Materials and Supplies	Materials and supplies in the consolidated balance sheets are carried at average costs and consist primarily of parts used in the repair and maintenance of track structure, equipment, and CSXT’s freight car and locomotive fleets, as well as fuel.
New Accounting Pronouncements	n February 2016, the FASB issued ASU, Leases , which requires lessees to recognize most leases on their balance sheets as a right-of-use asset with a corresponding lease liability. Lessor accounting under the standard is substantially unchanged. Additional qualitative and quantitative disclosures are also required. CSX adopted the standard effective January 1, 2019 using the cumulative-effect adjustment transition method, which applies the provisions of the standard at the effective date without adjusting the comparative periods presented. The Company adopted the following practical expedients and elected the following accounting policies related to this standard update: • Carry forward of historical lease classifications and current accounting treatment for existing land easements; • Short-term lease accounting policy election allowing lessees to not recognize right-of-use assets and liabilities for leases with a term of 12 months or less; and • The option to not separate lease and non-lease components for certain equipment lease asset categories such as freight car, vehicles and work equipment. Adoption of this standard resulted in the recognition of operating lease right-of-use assets and corresponding lease liabilities of $534 million on the consolidated balance sheet as of January 1, 2019 . This amount is lower than previous estimates due to a lease amendment. The Company’s accounting for finance leases remained substantially unchanged . The standard did not materially impact operating results or liquidity. Disclosures related to the amount, timing and uncertainty of cash flows arising from leases are included in Note 7, Leases . In June 2016, the FASB issued ASU Measurement of Credit Losses on Financial Instruments , which replaces current methods for evaluating impairment of financial instruments not measured at fair value, including trade accounts receivable and certain debt securities, with a current expected credit loss model. CSX adopted this new standard update effective January 1, 2020. Adoption will not have a material effect on the Company's results of operations.
Use of Estimates	The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires that management make estimates in reporting the amounts of certain assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amount of certain revenues and expenses during the reporting period. Actual results may differ from those estimates. Critical accounting estimates using management judgment are made for the following areas: • personal injury, environmental and legal reserves (see Note 5, Casualty, Environmental and Other Reserves ); • pension and post-retirement medical plan accounting (see Note 9, Employee Benefit Plans ); and • depreciation policies for assets under the group-life method (see Note 6, Properties ).
Earnings Per Share	Basic earnings per share is based on the weighted-average number of shares of common stock outstanding. Earnings per share, assuming dilution, is based on the weighted-average number of shares of common stock outstanding and common stock equivalents adjusted for the effects of common stock that may be issued as a result of potentially dilutive instruments. CSX's potentially dilutive instruments are made up of equity awards including performance units and employee stock options. When calculating diluted earnings per share, the potential shares that would be outstanding if all outstanding stock options were exercised are included. This number is different from outstanding stock options, which is included in Note 4, Stock Plans and Share-Based Compensation
Casualty Reserves	In accordance with the Contingencies Topic in the ASC, to the extent the value of an individual claim exceeds the self-insured retention amount, the Company would present the liability on a gross basis with a corresponding receivable for insurance recoveries. These reserves fluctuate based upon the timing of payments as well as changes in estimate. Actual results may vary from estimates due to the number, type and severity of the injury, costs of medical treatments and uncertainties in litigation. Defense and processing costs, which historically have been insignificant and are anticipated to be insignificant in the future, are not included in the recorded liabilities. Changes in casualty reserves are included in materials, supplies and other on the consolidated income statements. NOTE 5. Casualty, Environmental and Other Reserves, continued Personal Injury Personal injury reserves represent liabilities for employee work-related and third-party injuries. Work-related injuries for CSXT employees are primarily subject to the Federal Employers' Liability Act ("FELA"). CSXT retains an independent actuary to assist management in assessing the value of personal injury claims. An analysis is performed by the actuary quarterly and is reviewed by management. The methodology used by the actuary includes a development factor to reflect growth or reduction in the value of these personal injury claims based largely on CSXT's historical claims and settlement experience. This analysis did not result in a material adjustment to the personal injury reserve in 2019, 2018 or 2017. Occupational Occupational reserves represent liabilities for occupational disease and injury claims. Occupational disease claims arise primarily from allegations of exposure to asbestos in the workplace. Occupational injury claims arise from allegations of exposure to certain other materials in the workplace, such as solvents, soaps, chemicals (collectively referred to as “irritants”) and diesel fuels (like exhaust fumes) or allegations of chronic physical injuries resulting from work conditions, such as repetitive stress injuries. An analysis performed by management did not result in a material adjustment to the occupational reserve in 2019, 2018 or 2017.
Environmental Reserves	Environmental reserves were $74 million and $80 million for 2019 and 2018 , respectively. The Company is a party to various proceedings related to environmental issues, including administrative and judicial proceedings involving private parties and regulatory agencies. The Company has been identified as a potentially responsible party at approximately 220 environmentally impaired sites. Many of these are, or may be, subject to remedial action under the federal Comprehensive Environmental Response, Compensation and Liability Act of 1980 ("CERCLA"), also known as the Superfund Law, or similar state statutes. Most of these proceedings arose from environmental conditions on properties used for ongoing or discontinued railroad operations. A number of these proceedings, however, are based on allegations that the Company, or its predecessors, sent hazardous substances to facilities owned or operated by others for treatment, recycling or disposal. In addition, some of the Company’s land holdings were leased to others for commercial or industrial uses that may have resulted in releases of hazardous substances or other regulated materials onto the property and could give rise to proceedings against the Company. In any such proceedings, the Company is subject to environmental clean-up and enforcement actions under the Superfund Law, as well as similar state laws that may impose joint and several liability for clean-up and enforcement costs on current and former owners and operators of a site without regard to fault or the legality of the original conduct. These costs could be substantial. NOTE 5. Casualty, Environmental and Other Reserves, continued In accordance with the Asset Retirement and Environmental Obligations Topic in the ASC, the Company reviews its role with respect to each site identified at least quarterly, giving consideration to a number of factors such as: • type of clean-up required; • nature of the Company’s alleged connection to the location (e.g., generator of waste sent to the site or owner or operator of the site); • extent of the Company’s alleged connection (e.g., volume of waste sent to the location and other relevant factors); and • number, connection and financial viability of other named and unnamed potentially responsible parties at the location. Based on the review process, the Company has recorded amounts to cover contingent anticipated future environmental remediation costs with respect to each site to the extent such costs are reasonably estimable and probable. The recorded liabilities for estimated future environmental costs are undiscounted. The liability includes future costs for remediation and restoration of sites as well as any significant ongoing monitoring costs, but excludes any anticipated insurance recoveries. Payments related to these liabilities are expected to be made over the next several years. Environmental remediation costs are included in materials, supplies and other on the consolidated income statements. Currently, the Company does not possess sufficient information to reasonably estimate the amounts of additional liabilities, if any, on some sites until completion of future environmental studies. In addition, conditions that are currently unknown could, at any given location, result in additional exposure, the amount and materiality of which cannot presently be reasonably estimated. Based upon information currently available, however, the Company believes its environmental reserves accurately reflect the estimated cost of remedial actions currently required.
Capital Expenditures	The Company’s capital investment includes purchased and self-constructed assets and property additions that substantially extend the service life or increase the utility of those assets. Indirect costs that can be specifically traced to capital projects are also capitalized. The Company is committed to maintaining and improving its existing infrastructure and expanding its network capacity for long-term growth. Rail operations are capital intensive and CSX accounts for these costs in accordance with GAAP and the Company’s capitalization policy. All properties are stated at historical cost less an allowance for accumulated depreciation. The Company’s largest category of capital investment is the replacement of track assets and the acquisition or construction of new assets that enable CSX to enhance its operations or provide new capacity offerings to its customers. These construction projects are primarily completed by CSXT employees. Costs for track asset replacement and capacity projects that are capitalized include: • labor costs, because many of the assets are self-constructed; • costs to purchase or construct new track or to prepare ground for the laying of track; • welding (rail, field and plant) which are processes used to connect segments of rail; • new ballast, which is gravel and crushed stone that holds track in line; • fuels and lubricants associated with tie, rail and surfacing work which is the process of raising track to a designated elevation over an extended distance; • cross, switch and bridge ties which are the braces that support the rails on a track; • gauging which is the process of standardizing the distance between rails; • handling costs associated with installing rail, ties or ballast; • usage charge of machinery and equipment utilized in construction or installation; and • other track materials. Labor is a significant cost in self-constructed track replacement work. CSXT engineering employees directly charge their labor to the track replacement project (the capitalized depreciable property). In replacing track, these employees concurrently perform deconstruction and installation of track material. Because of this concurrent process, CSX must estimate the amount of labor that is related to deconstruction versus installation. As a component of the depreciation study for road and track assets, management performs an analysis of labor costs related to the self-constructed track replacement work, which includes direct observation of track replacement processes. Through this analysis, CSX determined that approximately 20% of labor costs associated with track replacement is related to the deconstruction of old track, for which certain elements are expensed, and 80% is associated with the installation of new track, which is capitalized. Capital investment related to locomotives and freight cars comprises the second largest category of the Company’s capital assets. This category includes purchases of locomotives and freight cars as well as certain equipment leases that are considered to be finance leases in accordance with the Leases Topic in the ASC. In addition, costs to modify or rebuild these assets are capitalized if the investment incurred extends the asset’s service life or improves utilization. Improvement projects must meet specified dollar thresholds to be capitalized and are reviewed by management to determine proper accounting treatment. Routine repairs, overhauls and other maintenance costs, for all asset categories, are expensed as incurred. Group-Life Assets Sales and Retirements Since the rail network is one contiguous, connected network it is impractical to maintain specific identification records for these assets. For track assets (e.g. rail, ties, and ballast), CSX utilizes a first-in, first-out approach to asset retirements. Equipment assets (e.g. locomotives and freight cars) are specifically identified at retirement. When an equipment asset is retired that has been depreciated using the group-life method, the cost is reduced from the cost base and recorded in accumulated depreciation. For sales or retirements of assets depreciated under the group-life method that occur in the ordinary course of business, the asset cost (net of salvage value or sales proceeds) is charged to accumulated depreciation and no gain or loss is immediately recognized. This practice is consistent with accounting treatment prescribed under the group-life method. As part of the depreciation study, an assessment of the recorded amount of accumulated depreciation is made to determine if it is deficient (or in excess) of the appropriate amount indicated by the study. Any such deficiency (or excess), including any deferred gains or losses, is amortized as a component of depreciation expense over the remaining service life of the asset group until the next required depreciation study. Since the overall assumption with the group-life method is that the assets within the group on average have the same service life and characteristics, it is therefore concluded that the deferred gains and losses offset over time. For sales or retirements of assets depreciated under the group-life method that do not occur in the ordinary course of business, a gain or loss may be recognized if the sale or retirement meets each of the following three criteria: (i) it is unusual, (ii) it is material in amount, and (iii) it varies significantly from the retirement profile identified through our depreciation studies. No material gains or losses were recognized on the sale of assets depreciated using the group-life method in 2019, 2018, or 2017 as no sales met the criteria described above. Land and Straight-line Assets Sales and Retirements
Depreciation Method	The depreciable assets of the Company are depreciated using either the group-life or straight-line method of accounting, which are both acceptable depreciation methods in accordance with GAAP. The Company depreciates its railroad assets, including main-line track, locomotives and freight cars, using the group-life method. Assets depreciated under the group-life method comprise 87% of total fixed assets of $45.1 billion on a gross basis as of December 2019. The remaining depreciable assets of the Company, including non-railroad assets and assets under finance leases, are depreciated using the straight-line method on a per asset basis. Land is not depreciated. The group-life method aggregates assets with similar lives and characteristics into groups and depreciates each of these groups as a whole. When using the group-life method, an underlying assumption is that each group of assets, as a whole, is used and depreciated to the end of its group’s recoverable life. The Company currently utilizes different depreciable asset categories to account for depreciation expense for the railroad assets that are depreciated under the group-life method. By utilizing various depreciable categories, the Company can more accurately account for the use of its assets. All assets of the Company are depreciated on a time or life basis. The group-life method of depreciation closely approximates the straight-line method of depreciation. Additionally, due to the nature of most of its assets (e.g. track is one contiguous, connected asset), the Company believes that this is the most accurate and effective way to properly depreciate its assets. Estimated Useful Life Management performs a review of depreciation expense and useful lives on a regular basis. Under the group-life method, the service lives and salvage values for each group of assets are determined by completing periodic depreciation studies and applying management’s methods to determine the service lives of its properties. A depreciation study is the periodic review of asset service lives, salvage values, accumulated depreciation, and other related factors for group assets conducted by a third-party specialist, analyzed by the Company’s management and approved by the STB, the regulatory board that has broad jurisdiction over railroad practices. The STB requires depreciation studies be performed every three years for equipment assets (e.g. locomotives and freight cars) and every six years for road and track assets (e.g. bridges, signals, rail, ties, and ballast). The Company believes the frequency of depreciation studies currently required by the STB, complemented by annual data reviews conducted by a third-party specialist and analyzed by the Company's management, provides adequate review of asset service lives and that a more frequent review would not result in a material change due to the long-lived nature of most of the assets.
Impairment Review	Properties and other long-lived assets are reviewed for impairment whenever events or business conditions indicate the carrying amount of such assets may not be fully recoverable. Initial assessments of recoverability are based on estimates of undiscounted future net cash flows associated with an asset or a group of assets in accordance with the Property, Plant, and Equipment Topic
Revenue Recognition	The Company generates revenue from freight billings under contracts with customers generally on a rate per carload, container or ton-basis based on length of haul and commodities carried. The Company’s performance obligation arises when it receives a bill of lading (“BOL”) to transport a customer's commodities at a negotiated price contained in a transportation services agreement or a publicly disclosed tariff rate. Once a BOL is received, a contract is formed whereby the parties are committed to perform, collectability of consideration is probable and the rights of the parties, shipping terms and conditions, and payment terms are identified. A customer may submit several BOLs for transportation services at various times throughout a service agreement term but each shipment represents a distinct service that is a separately identified performance obligation. The average transit time to complete a shipment is between 3 to 8 days depending on market. Payments for transportation services are normally billed once a BOL is received and are generally due within 15 days after the invoice date. The Company recognizes revenue over transit time of freight as it moves from origin to destination. Revenue for services started but not completed at the reporting date is allocated based on the relative transit time in each reporting period, with the portion allocated for services subsequent to the reporting date considered remaining performance obligations. NOTE 11. Revenues, continued The certain key estimates included in the recognition and measurement of revenue and related accounts receivable are as follows: • Revenue associated with shipments in transit is recognized ratably over transit time and is based on average cycle times to move commodities and products from their origin to their final destination or interchange; • Adjustments to revenue for billing corrections and billing discounts; • Adjustments to revenue for overcharge claims filed by customers, which are based on historical payments to customers for rate overcharges as a percentage of total billing; and • Incentive-based refunds to customers, which are primarily volume-related, are recorded as a reduction to revenue on the basis of the projected liability (this estimate is based on historical activity, current volume levels and forecasted future volume). Revenue related to interline transportation services that involve the services of another party, such as another railroad, is reported on a net basis. The portion of the gross amount billed to customers that is remitted by the Company to another party is not reflected as revenue. Other revenue is comprised of revenue from regional subsidiary railroads and incidental charges , including demurrage and switching. It is recorded upon completion of the service and accounts for an immaterial percentage of the Company’s total revenue. Revenue from regional subsidiary railroads includes shipments by railroads that the Company does not directly operate. Demurrage represents charges assessed when freight cars are held by a customer beyond a specified period of time. Switching represents charges assessed when a railroad switches cars for a customer or another railroad. During 2019 , 2018 and 2017 , revenue recognized from performance obligations related to prior periods (for example, due to changes in transaction price), was not material. Remaining Performance Obligations Remaining performance obligations represent the transaction price allocated to future reporting periods for freight services started but not completed at the reporting date . This includes the unearned portion of billed and unbilled amounts for cancellable freight shipments in transit. The Company expects to recognize the unearned portion of revenue for freight services in transit within one week of the reporting date. As of December 31, 2019 , remaining performance obligations were not material. Contract Balances and Accounts Receivable The Company’s revenues are primarily derived from the transportation of freight as performance obligations that arise from its contracts with customers are satisfied. The following table presents the Company’s revenues disaggregated by market as this best depicts how the nature, amount, timing and uncertainty of revenue and cash flows are affected by economic factors.
Leases	Finance leases are included in properties-net and long-term debt on the consolidated balance sheets and were not material as of December 2019 or December 2018. The associated amortization expense and interest expense are included in depreciation and interest expense, respectively, on the consolidated income statements CSX has various lease agreements with terms up to 50 years , including leases of land, land with integral equipment (e.g. track), buildings and various equipment. Some leases include options to purchase, terminate or extend for one or more years. These options are included in the lease term when it is reasonably certain that the option will be exercised. At inception, the Company determines if an arrangement contains a lease and whether that lease meets the classification criteria of a finance or operating lease. Some of the Company’s lease arrangements contain lease components (e.g. minimum rent payments) and non-lease components (e.g. maintenance, labor charges, etc.). The Company generally accounts for each component separately based on the estimated standalone price of each component. For certain equipment leases, such as freight car, vehicles and work equipment, the Company accounts for the lease and non-lease components as a single lease component. Certain of the Company’s lease agreements include rental payments that are adjusted periodically for an index or rate. The leases are initially measured using the projected payments adjusted for the index or rate in effect at the commencement date. The Company’s lease agreements do not contain any material residual value guarantees or material restrictive covenants. Operating Leases Operating leases are included in right-of-use lease assets, other current liabilities and long-term lease liabilities on the consolidated balance sheets. These assets and liabilities are recognized at the commencement date based on the present value of remaining lease payments over the lease term using the Company’s secured incremental borrowing rates or implicit rates, when readily determinable. Short-term operating leases, which have an initial term of 12 months or less, are not recorded on the balance sheet. The Company has various lease agreements with other parties with terms up to 50 years . Non-cancelable, long-term leases may include provisions for maintenance, options to purchase and options to extend the terms. Lease expense for operating leases, including leases with escalations over their terms, is recognized on a straight-line basis over the lease term. Variable lease expense is recognized in the period in which the obligation for those payments is incurred. Lease expense is included in equipment and other rents on the consolidated income statements and is reported net of lease income. Lease income was not material to the results of operations for 2019, 2018 or 2017.

Nature of Operations and Sign_3

Nature of Operations and Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Restructuring of Expenses Related to Management Workforce Reduction and Other Restructuring Costs	xpenses related to the management workforce reduction and other restructuring costs totaled $325 million in 2017 and are shown in the following table. Fiscal Year 2017 (Dollars in millions) Operating Restructuring Charge Non-Operating Restructuring Charge Severance and Pension $ 98 $ 56 Other Post-Retirement Benefits Curtailment — 17 Employee Equity Awards Proration and Other 23 — Subtotal Management Workforce Reduction $ 121 $ 73 Reimbursement Arrangements 84 — Executive Equity Awards Proration 24 — Pension Settlement Charge — 12 Advisory Fees Related to Shareholder Matters 11 — Total Restructuring Charge $ 240 $ 85

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
Earnings Per Share (Tables)	Dec. 31, 2019
Earnings Per Share [Abstract]
Schedule of Computation of Basic and Diluted Earnings per Share	The following table sets forth the computation of basic earnings per share and earnings per share, assuming dilution: Fiscal Years 2019 2018 2017 Numerator (Dollars in Millions) : Net Earnings $ 3,331 $ 3,309 $ 5,471 Dividend Equivalents on Restricted Stock — (1 ) (1 ) Net Earnings, Attributable to Common Shareholders $ 3,331 $ 3,308 $ 5,470 Denominator (Units in Millions) : Average Common Shares Outstanding 796 857 911 Other Potentially Dilutive Common Shares 2 4 3 Average Common Shares Outstanding, Assuming Dilution 798 861 914 Net Earnings Per Share, Basic $ 4.18 $ 3.86 $ 6.01 Net Earnings Per Share, Assuming Dilution $ 4.17 $ 3.84 $ 5.99
Schedule of Share Repurchase Activity	During 2019, 2018, and 2017, CSX repurchased the following shares: Fiscal Years 2019 2018 2017 Shares Repurchased (Units in Millions) 48 72 39 Cost of Shares (Dollars in Millions) $ 3,373 $ 4,671 $ 1,970 Average Price Paid per Share $ 70.54 $ 64.64 $ 50.80

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	12 Months Ended
Shareholders' Equity (Tables)	Dec. 31, 2019
Stockholders' Equity Note [Abstract]
Schedule of Common and Preferred Stock	Common and preferred stock consists of the following: Common Stock, $1 Par Value December 2019 (Units in Millions) Common Shares Authorized 1,800 Common Shares Issued and Outstanding 773 Preferred Stock Preferred Shares Authorized 25 Preferred Shares Issued and Outstanding —

Stock Plans and Share-Based C_2

Stock Plans and Share-Based Compensation (Tables)	12 Months Ended
Stock Plans and Share-Based Compensation (Tables)	Dec. 31, 2019
Share-based Payment Arrangement [Abstract]
Schedule of Share-Based Compensation and Related Income Tax Benefit	Total pre-tax expense and income tax benefits associated with share-based compensation are shown in the table below. Income tax benefits include impacts from option exercises and the vesting of other equity awards. Modifications to the terms of awards (see Equity Award Modifications below) impacted share-based compensation expense in 2017. Fiscal Years (Dollars in Millions) 2019 2018 2017 Share-Based Compensation Expense Performance Units $ 42 $ 28 $ 49 Stock Options 18 13 22 Restricted Stock Units and Awards 8 6 15 Stock Awards for Directors 2 2 3 Employee Stock Purchase Plan 4 2 — Total Share-based Compensation Expense $ 74 $ 51 $ 89 Income Tax Benefit $ 43 $ 26 $ 42
Schedule of Assumptions and Inputs Used to Estimate Fair Value of Performance Units	The fair value of the performance units awarded during the years ended December 2019 and 2018 were calculated using a Monte-Carlo simulation model with the following weighted-average assumptions: Weighted-average assumptions used: 2019 2018 Annual dividend yield 1.4 % 1.6 % Risk-free interest rate 2.4 % 2.3 % Annualized volatility 27.4 % 29.1 % Expected life (in years) 2.8 2.9
Schedule of Performance Unit Grant and Vesting Information	Performance unit grant and vesting information is summarized as follows: Fiscal Years 2019 2018 2017 Weighted-average grant date fair value $ 66.18 $ 55.57 $ 49.50 Fair value of units vested in fiscal year ending (in millions) $ 17 $ 14 $ 26
Schedule of Performance Unit Activity Related to Outstanding Long-term Incentive Plans and Corresponding Fair Value	The performance unit activity related to the outstanding long-term incentive plans and corresponding fair value is summarized as follows: Performance Units Outstanding Weighted-Average Fair Value at Grant Date Unvested at December 31, 2018 722 $ 52.58 Granted 337 66.18 Forfeited (75 ) 57.20 Vested (341 ) 49.52 Unvested at December 31, 2019 643 $ 60.58
Schedule of Assumptions and Inputs Used to Estimate Fair Value of Stock Options	Assumptions and inputs used to estimate fair value of stock options are summarized as follows: Fiscal Years 2019 2018 2017 Weighted-average grant date fair value $ 17.87 $ 14.65 $ 12.84 Stock options valuation assumptions: Annual dividend yield 1.3 % 1.5 % 1.5 % Risk-free interest rate 2.4 % 2.6 % 2.2 % Annualized volatility 25.7 % 27.0 % 27.1 % Expected life (in years) 6.1 6.5 6.3 Other pricing model inputs: Weighted-average grant-date market price of CSX stock (strike price) $ 70.01 $ 54.19 $ 49.63
Schedule of Stock Option Activity	The stock option activity is summarized as follows: Stock Options Outstanding Weighted-Average Exercise Price Weighted-Average Remaining Contractual Life Aggregate Intrinsic Value Outstanding at December 31, 2018 4,673 $ 34.89 Granted 1,187 70.01 Forfeited (212 ) 55.35 Exercised (1,853 ) 24.48 Outstanding at December 31, 2019 3,795 $ 49.78 7.5 $ 87 Exercisable at December 31, 2019 1,026 $ 24.60 6.0 $ 49
Schedule of Intrinsic Value and Cash Proceeds of Options Exercises	There were no significant exercises during 2017 or 2018. Additional information on stock option exercises in 2019 is summarized as follows: (Dollars in Millions) 2019 Intrinsic value of stock options exercised $ 87 Cash received from option exercises $ 45
Schedule of Restricted Stock Grant and Vesting Information	Restricted stock grant and vesting information is summarized as follows: Fiscal Years 2019 2018 2017 Weighted-average grant date fair value $ 69.19 $ 62.60 $ 48.35 Fair value of units and awards vested during fiscal year ended (in millions) $ 7 $ 9 $ 8
Schedule of Outstanding Restricted Stock Units and Awards	The restricted stock activity related to the outstanding long-term incentive plans and other awards and corresponding fair value is summarized as follows: Restricted Stock Units and Awards Outstanding Weighted-Average Fair Value at Grant Date Unvested at December 31, 2018 684 $ 39.30 Granted 88 69.19 Forfeited (30 ) 53.28 Vested (315 ) 24.21 Unvested at December 31, 2019 427 $ 57.29

Casualty, Environmental and O_2

Casualty, Environmental and Other Reserves (Tables)	12 Months Ended
Casualty, Environmental and Other Reserves (Tables)	Dec. 31, 2019
Casualty, Environmental and Other Reserves [Abstract]
Schedule of Claims Activity	Activity related to casualty, environmental and other reserves is as follows: Casualty Environmental Other (Dollars in Millions) Reserves Reserves Reserves Total December 30, 2016 $ 229 $ 95 $ 50 $ 374 Charged to Expense 43 26 45 114 Payments (44 ) (31 ) (39 ) (114 ) December 31, 2017 228 90 56 374 Charged to Expense 21 10 41 72 Payments (50 ) (20 ) (52 ) (122 ) December 31, 2018 199 80 45 324 Charged to Expense 56 17 34 107 Payments (68 ) (23 ) (35 ) (126 ) December 31, 2019 $ 187 $ 74 $ 44 $ 305
Schedule of Balance Sheet Presentation of Casualty, Environmental and Other Reserves	Casualty, environmental and other reserves are provided for in the consolidated balance sheets as shown in the table below. December 2019 December 2018 (Dollars in Millions) Current Long-term Total Current Long-term Total Casualty: Personal Injury $ 42 $ 87 $ 129 $ 40 $ 103 $ 143 Occupational 6 52 58 10 46 56 Total Casualty $ 48 $ 139 $ 187 $ 50 $ 149 $ 199 Environmental 31 43 74 39 41 80 Other 21 23 44 24 21 45 Total $ 100 $ 205 $ 305 $ 113 $ 211 $ 324

Properties (Tables)

Properties (Tables)	12 Months Ended
Properties (Tables)	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Schedule of Net Properties	A detail of the Company’s net properties are as follows: (Dollars in Millions) Accumulated Net Book Annual Depreciation Estimated Useful Life Depreciation December 2019 Cost Depreciation Value Rate ( Avg. Years) Method Road Rail and Other Track Material $ 8,194 $ (1,719 ) $ 6,475 2.5% 40 Group Life Ties 6,041 (1,666 ) 4,375 3.7% 27 Group Life Grading 2,763 (595 ) 2,168 1.4% 72 Group Life Ballast 3,156 (1,013 ) 2,143 2.7% 37 Group Life Bridges, Trestles, and Culverts 2,529 (334 ) 2,195 1.6% 61 Group Life Signals and Interlockers 3,077 (819 ) 2,258 4.0% 25 Group Life/ Straight Line (a) Buildings 1,335 (492 ) 843 2.5% 40 Group Life Other 5,030 (1,980 ) 3,050 4.2% 24 Group Life Total Road 32,125 (8,618 ) 23,507 Equipment Locomotive 5,320 (2,020 ) 3,300 3.6% 27 Group Life Freight Cars 2,964 (880 ) 2,084 2.9% 35 Group Life Work Equipment and Other 2,424 (1,414 ) 1,010 8.2% 12 Group Life/ Straight Line (a) Total Equipment 10,708 (4,314 ) 6,394 Land 1,836 — 1,836 N/A N/A N/A Construction In Progress 431 — 431 N/A N/A N/A Total Properties $ 45,100 $ (12,932 ) $ 32,168 (a) For depreciation method, certain asset categories contain intermodal terminals or technology-related assets, which are depreciated using the straight-line method. NOTE 6. Properties, continued (Dollars in Millions) Accumulated Net Book Annual Depreciation Estimated Useful Life Depreciation December 2018 Cost Depreciation Value Rate (Avg. Years) Method Road Rail and Other Track Material $ 7,964 $ (1,698 ) $ 6,266 2.5% 40 Group Life Ties 5,860 (1,557 ) 4,303 3.7% 27 Group Life Grading 2,757 (572 ) 2,185 1.4% 72 Group Life Ballast 3,076 (971 ) 2,105 2.7% 37 Group Life Bridges, Trestles, and Culverts 2,506 (382 ) 2,124 1.6% 61 Group Life Signals and Interlockers 2,975 (693 ) 2,282 4.0% 25 Group Life/ Straight Line (a) Buildings 1,318 (486 ) 832 2.5% 40 Group Life Other 4,955 (1,964 ) 2,991 4.2% 24 Group Life Total Road 31,411 (8,323 ) 23,088 Equipment Locomotive 5,661 (2,266 ) 3,395 3.5% 29 Group Life Freight Cars 3,093 (882 ) 2,211 2.9% 35 Group Life Work Equipment and Other 2,338 (1,336 ) 1,002 7.4% 14 Group Life/ Straight Line (a) Total Equipment 11,092 (4,484 ) 6,608 Land 1,845 — 1,845 N/A N/A N/A Construction In Progress 457 — 457 N/A N/A N/A Total Properties $ 44,805 $ (12,807 ) $ 31,998 (a) For depreciation method, certain asset categories contain intermodal terminals or technology-related assets, which are depreciated using the straight-line method.

Leases (Tables)

Leases (Tables)	12 Months Ended
Leases (Tables)	Dec. 31, 2019
Leases [Abstract]
Schedule of Information Company’s Operating Leases	A significant operating lease was renewed in 2018 with the State of Georgia for approximately 137 miles of right-of-way with integral equipment for an additional term of 50 years with an annual 2.5% increase. The following table presents information about the amount, timing and uncertainty of cash flows arising from the Company’s operating leases as of December 31, 2019 . (Dollars in Millions) December 2019 Maturity of Lease Liabilities Lease Payments 2020 58 2021 54 2022 48 2023 39 2024 37 Thereafter 1,208 Total undiscounted operating lease payments $ 1,444 Less: Imputed interest (894 ) Present value of operating lease liabilities $ 550 Balance Sheet Classification Current lease liabilities (recorded in other current liabilities) $ 57 Long-term lease liabilities 493 Total operating lease liabilities $ 550 Other Information Weighted-average remaining lease term for operating leases 33 years Weighted-average discount rate for operating leases 5.0 %
Schedule of Operating Lease Costs	These amounts are shown in the table below. Fiscal Years (Dollars in Millions) 2019 2018 2017 Rent Expense on Operating Leases $ 84 $ 66 $ 78

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
Commitments and Contingencies (Tables)	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Schedule of Number of Locomotives and Payments under Long-term Maintenance Program	The following table summarizes the number of locomotives covered and CSXT’s payments under the long-term maintenance program. Fiscal Years (Dollars in Millions) 2019 2018 2017 Amounts Paid $ 139 $ 170 $ 197 Number of Locomotives 1,897 1,910 2,062
Schedule of Annual Payments under Long-term Maintenance Program	Total annual payments under all of these purchase commitments are also estimated in the table below. (Dollars in Millions) Locomotive Maintenance & Rebuild Payments Other Commitments Total 2020 $ 233 $ 59 $ 292 2021 178 19 197 2022 211 18 229 2023 237 17 254 2024 273 17 290 Thereafter 2,337 111 2,448 Total $ 3,469 $ 241 $ 3,710

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	12 Months Ended
Employee Benefit Plans (Tables)	Dec. 31, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Abstract]
Summary of Participants	In order to perform this valuation, the actuaries are provided with the details of the population covered at the beginning of the year, summarized in the table below, and projects that population forward to the end of the year . Summary of Participants as of January 1, 2019 Pension Plans Post-retirement Medical Plan Active Employees 3,521 616 Retirees and Beneficiaries 12,016 8,393 Other (a) 4,012 40 Total 19,549 9,049 (a) For pension plans, the other category consists mostly of terminated but vested former employees. For post-retirement plans, the other category consists of employees on long-term disability that have not yet retired.
Schedule of Future Expected Benefit Payments	Future expected benefit payments are as follows: Expected Cash Flows (Dollars in Millions) Pension Benefits Post-retirement Benefits 2020 $ 193 $ 20 2021 188 12 2022 186 10 2023 184 9 2024 182 9 2025-2029 897 34 Total $ 1,830 $ 94
Schedule of Allocation of Plan Assets	The distribution of pension plan assets as of the measurement date is shown in the table below, and these assets are reported net of pension liabilities on the balance sheet. December 2019 December 2018 Percent of Percent of (Dollars in Millions) Amount Total Assets Amount Total Assets Equity $ 1,770 63 % $ 1,698 70 % Fixed Income 818 29 704 29 Cash and Cash Equivalents 237 8 29 1 Total $ 2,825 100 % $ 2,431 100 %
Schedule of Changes in Benefit Obligation and Fair Value of Plan Assets	Changes in benefit obligation and the fair value of plan assets for the 2019 and 2018 calendar plan years are as follows: Pension Benefits Post-retirement Benefits Plan Year Plan Year Plan Year Plan Year (Dollars in Millions) 2019 2018 2019 2018 Actuarial Present Value of Benefit Obligation Accumulated Benefit Obligation $ 2,963 $ 2,623 N/A N/A Projected Benefit Obligation 3,122 2,758 $ 117 $ 118 Change in Projected Benefit Obligation: Projected Benefit Obligation at Beginning of Plan Year $ 2,758 $ 3,002 $ 118 $ 250 Service Cost (a) 34 36 1 2 Interest Cost 103 92 2 7 Plan Participants' Contributions — — 7 5 Post-retirement Plan Amendment — — — (102 ) Actuarial Loss (Gain) 418 (173 ) 22 (10 ) Benefits Paid (191 ) (199 ) (33 ) (34 ) Benefit Obligation at End of Plan Year $ 3,122 $ 2,758 $ 117 $ 118 Change in Plan Assets: Fair Value of Plan Assets at Beginning of Plan Year $ 2,431 $ 2,833 $ — $ — Actual Return on Plan Assets Gain (Loss) 568 (220 ) — — Non-qualified Employer Contributions 17 17 26 30 Plan Participants' Contributions — — 7 4 Benefits Paid (191 ) (199 ) (33 ) (34 ) Fair Value of Plan Assets at End of Plan Year 2,825 2,431 — — Funded Status at End of Plan Year $ (297 ) $ (327 ) $ (117 ) $ (118 ) (a) Service cost for each 2019 and 2018 includes capitalized service costs of $3 million .
Schedule of Amount Recognized in Balance Sheet	Amounts related to pension and post-retirement benefits recorded in other long-term assets, labor and fringe benefits payable and other long-term liabilities on the balance sheet are as follows: Pension Benefits Post-retirement Benefits December December December December (Dollars in Millions) 2019 2018 2019 2018 Amounts Recorded in Consolidated Balance Sheets: Long-term Assets (a) $ 25 $ 13 $ — $ — Current Liabilities (17 ) (16 ) (20 ) (34 ) Long-term Liabilities (305 ) (324 ) (97 ) (84 ) Net Amount Recognized in Consolidated Balance Sheets $ (297 ) $ (327 ) $ (117 ) $ (118 ) (a) Long-term assets as of December 2019 and 2018 relate to qualified pension plans where assets exceed projected benefit obligations.
Schedule of Benefit Obligations in Excess of Plan Assets	At December 2019, the status of CSX plans with a net liability only is disclosed below. The total fair value of all plan assets as of December 2019 was $2.8 billion , which includes the qualified pension plans with net assets. Aggregate (Dollars in Millions) Fair Value Aggregate Benefit Obligations in Excess of Plan Assets of Plan Assets Benefit Obligation Projected Benefit Obligation $ 2,715 $ (3,037 ) Accumulated Benefit Obligation 2,715 (2,878 )
Schedule of Net Benefit Expense	The following table describes the components of expense/(income) related to net benefit expense recorded on the income statement. Pension Benefits Fiscal Years Post-retirement Benefits Fiscal Years (Dollars in Millions) 2019 2018 2017 2019 2018 2017 Service Cost Included in Labor and Fringe $ 31 $ 32 $ 36 $ 1 $ 2 $ 2 Interest Cost 103 92 92 2 7 7 Expected Return on Plan Assets (171 ) (176 ) (171 ) — — — Amortization of Net Loss 30 41 41 — — — Amortization of Prior Service Cost — — — (7 ) (2 ) — Total Income Included in Other Income - Net (38 ) (43 ) (38 ) (5 ) 5 7 Net Periodic Benefit (Credit) Expense $ (7 ) $ (11 ) $ (2 ) $ (4 ) $ 7 $ 9 Restructuring Charge - Non Operating (a) — — 60 — — 13 Settlement (Gain) Loss — (1 ) 11 — — — Total (Credit) Expense $ (7 ) $ (12 ) $ 69 $ (4 ) $ 7 $ 22 (a) Charges related to special termination benefits and curtailment costs were the result of the management workforce reductions in first quarter 2017. See Restructuring Charge in Note 1, Nature of Operations and Significant Accounting Policies.
Schedule of Pre-tax Change in Other Comprehensive Loss (Income)	The following table shows the pre-tax change in other comprehensive loss (income) attributable to certain components of net benefit expense and the change in benefit obligation for CSX for pension and other post-employment benefits. (Dollars in Millions) Pension Benefits Post-retirement Benefits Components of Other Comprehensive December December December December Loss (Income) 2019 2018 2019 2018 Recognized in the Balance Sheet Losses (Gains) $ 21 $ 223 $ 22 $ (112 ) Expense (Income) Recognized in the Income Statement Amortization of Net Losses (a) $ 30 $ 41 $ — $ — Settlement (Gain) Loss — (1 ) — — Amortization of Prior Service Costs — — (7 ) (2 ) (a) Amortization of net losses estimated to be expensed for 2020 is approximately $57 million for pension benefits.
Schedule of Weighted-Average Assumptions Used	The weighted averages of assumptions used by the Company to value its pension and post-retirement obligations were as follows: Pension Benefits Post-retirement Benefits 2019 2018 2019 2018 Expected Long-term Return on Plan Assets: Benefit Cost for Current Plan Year 6.75 % 6.75 % N/A N/A Benefit Cost for Subsequent Plan Year 6.75 % 6.75 % N/A N/A Discount Rates: Benefit Cost for Plan Year Service Cost for Plan Year 4.40 % 3.74 % 4.14 % 4.14 % (a) Interest Cost for Plan Year 3.87 % 3.15 % 3.51 % 3.45 % (a) Benefit Obligation at End of Plan Year 3.13 % 4.24 % 2.87 % 3.98 % Salary Scale Inflation 4.60 % 4.60 % N/A N/A (a) The post-retirement benefits service cost and interest cost for 2018 were based on a weighted average discount rate of 3.68% and 2.79% , respectively, prior to the post-retirement plan amendments approved in 2018 and were increased to 4.14% and 3.45% , respectively, after the Company remeasured the other post-retirement benefits obligation in the fourth quarter of 2018.

Debt and Credit Agreements (Tab

Debt and Credit Agreements (Tables)	12 Months Ended
Debt and Credit Agreements (Tables)	Dec. 31, 2019
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments	Debt at December 2019 and December 2018 is shown in the table below. For information regarding the fair value of debt, see Note 13, Fair Value Measurements. Maturity at December Average Interest Rates at December December December (Dollars in Millions) 2019 2019 2019 2018 Notes 2020-2068 4.4% $ 16,056 $ 14,558 Equipment Obligations (a) 2020-2023 6.3% 178 195 Finance Leases 2020-2026 15.0% 4 4 Subtotal Long-term Debt (including current portion) $ 16,238 $ 14,757 Less Debt Due within One Year (245 ) (18 ) Long-term Debt (excluding current portion) $ 15,993 $ 14,739 (a) Equipment obligations are secured by an interest in certain railroad equipment.
Schedule of Long-term Debt Maturities	Long-term Debt Maturities (Net of Discounts, Premiums and Issuance Costs) (Dollars in Millions) Maturities at Fiscal Years Ending December 2019 2020 $ 245 2021 401 2022 162 2023 639 2024 551 Thereafter 14,240 Total Long-term Debt Maturities, including current portion $ 16,238

Revenues (Tables)

Revenues (Tables)	12 Months Ended
Revenues (Tables)	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Schedule of Revenues Disaggregated by Lines of Business	The following table presents the Company’s revenues disaggregated by market as this best depicts how the nature, amount, timing and uncertainty of revenue and cash flows are affected by economic factors. Fiscal Years (Dollars in millions) 2019 2018 2017 Chemicals $ 2,343 $ 2,339 $ 2,210 Agricultural and Food Products 1,410 1,306 1,262 Automotive 1,236 1,267 1,195 Forest Products 878 850 755 Metals and Equipment 741 769 703 Minerals 550 518 477 Fertilizers 431 442 466 Total Merchandise 7,589 7,491 7,068 Coal 2,070 2,246 2,107 Intermodal 1,760 1,931 1,799 Other 518 582 434 Total $ 11,937 $ 12,250 $ 11,408
Schedule of Accounts Receivable - Net	The Company’s accounts receivable - net consists of freight and non-freight receivables, reduced by an allowance for doubtful accounts. (Dollars in millions) December 31, December 31, Freight Receivables $ 790 $ 846 Freight Allowance for Doubtful Accounts (21 ) (18 ) Freight Receivables, net 769 828 Non-Freight Receivables 226 190 Non-Freight Allowance for Doubtful Accounts (9 ) (8 ) Non-Freight Receivables, net 217 182 Total Accounts Receivable, net $ 986 $ 1,010

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
Income Taxes (Tables)	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Schedule of Breakdown of Income Tax Expense Between Current and Deferred	The breakdown of income tax expense between current and deferred is as follows: Fiscal Years (Dollars in Millions) 2019 2018 2017 Current: Federal $ 608 $ 572 $ 787 State 104 144 117 Subtotal Current 712 716 904 Deferred: Federal 235 275 (3,277 ) State 38 4 44 Subtotal Deferred 273 279 (3,233 ) Total $ 985 $ 995 $ (2,329 )
Schedule of Income Tax Expense Reconciled to Tax Computed at Statutory Rates	Income tax expense reconciled to the tax computed at statutory rates is presented in the following table. Fiscal Years (Dollars In Millions) 2019 2018 2017 Federal Income Taxes $ 906 21.0 % $ 904 21.0 % $ 1,100 35.0 % State Income Taxes 108 2.5 % 112 2.6 % 102 3.2 % Deferred Tax Rate Change — — % — — % (3,506 ) (111.6 )% Other (29 ) (0.7 )% (21 ) (0.5 )% (25 ) (0.8 )% Income Tax (Benefit) Expense/Rate $ 985 22.8 % $ 995 23.1 % $ (2,329 ) (74.2 )%
Schedule of Significant Components of Deferred Income Tax Assets and Liabilities	The significant components of deferred income tax assets and liabilities include: 2019 2018 (Dollars in Millions) Assets Liabilities Assets Liabilities Pension Plans $ 71 $ — $ 79 $ — Other Employee Benefit Plans 127 — 146 — Accelerated Depreciation — 7,020 — 6,799 Other 426 565 529 645 Total $ 624 $ 7,585 $ 754 $ 7,444 Net Deferred Income Tax Liabilities $ 6,961 $ 6,690

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
Fair Value Measurements (Tables)	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Schedule of Fair Value of Investment Assets	The Company's investment assets are carried at fair value on the consolidated balance sheets as summarized in the following table. All of the inputs used to determine the fair value of the Company's investments are Level 2 inputs. The amortized cost basis of these investments was $1.1 billion and $340 million as of December 31, 2019 and December 31, 2018 , respectively. Fiscal Years 2019 2018 (Dollars in Millions) Level 2 Level 2 Certificates of Deposit and Commercial Paper $ 989 $ 250 Corporate Bonds 59 56 Government Securities 36 35 Total investments at fair value $ 1,084 $ 341
Schedule of Investment Maturities	These investments have the following maturities and are represented on the consolidated balance sheet within short-term investments for investments with maturities of less than one year, and other long-term assets for investments with maturities of one year and greater: (Dollars in Millions) December 2019 December 2018 Less than 1 year $ 996 $ 253 1 - 5 years 10 14 5 - 10 years 25 26 Greater than 10 years 53 48 Total investments at fair value $ 1,084 $ 341
Schedule of Fair Value and Carrying Value of Long-term Debt	The fair value and carrying value of the Company's long-term debt is as follows: (Dollars in Millions) December 2019 December 2018 Long-term Debt (Including Current Maturities): Fair Value $ 18,503 $ 14,914 Carrying Value 16,238 14,757
Schedule of Pension Plan Assets at Fair Value by Level	The pension plan assets at fair value by level, within the fair value hierarchy, as of calendar plan years 2019 and 2018 are shown in the table below. For additional information related to pension assets, see Note 9, Employee Benefit Plans. Fiscal Years 2019 2018 (Dollars in Millions) Level 1 Level 2 Total Level 1 Level 2 Total Common Stock $ 823 $ — $ 823 $ 750 $ — $ 750 Mutual funds 78 — 78 7 — 7 Cash and cash equivalents 229 — 229 3 — 3 Corporate bonds — 588 588 — 537 537 Government securities — 217 217 — 149 149 Asset-backed securities — 8 8 — 10 10 Derivatives and other — 9 9 — 5 5 Total investments in the fair value hierarchy $ 1,130 $ 822 $ 1,952 $ 760 $ 701 $ 1,461 Investments measured at net asset value (a) n/a n/a $ 873 n/a n/a $ 970 Investments at fair value $ 1,130 $ 822 $ 2,825 $ 760 $ 701 $ 2,431

Other Income - Net (Tables)

Other Income - Net (Tables)	12 Months Ended
Other Income - Net (Tables)	Dec. 31, 2019
Other Income and Expenses [Abstract]
Schedule of Other Income - Net	Other income – net consisted of the following: Fiscal Years (Dollars in Millions) 2019 2018 2017 Net Periodic Pension and Post-retirement Benefit Credit (a) $ 43 $ 38 $ 32 Interest Income 48 32 13 Miscellaneous (Expense) Income (3 ) 4 8 Total Other Income - Net $ 88 $ 74 $ 53

Related Parties and Affiliates

Related Parties and Affiliates (Tables)	12 Months Ended
Related Parties and Affiliates (Tables)	Dec. 31, 2019
Related Party Transactions [Abstract]
Schedule of Future Payments Under Shared Asset Area Agreements	Future payments due to Conrail under the shared asset area agreements are shown in the table below. (Dollars in Millions) Conrail Shared Years Asset Agreement 2020 $ 29 2021 29 2022 29 2023 29 2024 22 Thereafter — Total $ 138
Schedule of Related Party in the Consolidated Income Statement Components	The following table discloses amounts related to Conrail. Purchase price amortization and equity earnings are included in equity earnings of affiliates and all other amounts in the table are included in materials, supplies and other expenses on the Company’s consolidated income statements. Fiscal Years (Dollars in Millions) 2019 2018 2017 Rents, fees and services $ 119 $ 117 $ 120 Purchase price amortization and other 4 4 4 Equity earnings of Conrail (42 ) (43 ) (58 ) Total Conrail Expense $ 81 $ 78 $ 66 As required by the Related Party Disclosures Topic in the ASC, the following table discloses amounts related to TTX. Car hire rents are included in equipment and other rents expense and equity earnings are included in equity earnings of affiliates in the Company’s consolidated income statements. Also included below is balance sheet information related to CSX's payable to TTX, which represents car rental liabilities. Fiscal Years (Dollars in Millions) 2019 2018 2017 Income statement information: Car hire rents $ 223 $ 223 $ 237 Equity earnings of TTX (56 ) (60 ) (157 ) Total TTX expense $ 167 $ 163 $ 80
Schedule of Related Party Consolidated Balance Sheet Components	As required by the Related Party Disclosures Topic in the ASC, the Company has identified amounts below owed to Conrail, or its subsidiaries, representing liabilities under the operating, equipment and shared area agreements with Conrail. In 2014, the Company executed two promissory notes with a subsidiary of Conrail which were included in long-term debt on the consolidated balance sheets. Interest expense from these promissory notes was $6 million in each 2019 , 2018 and 2017 . December December (Dollars in Millions) 2019 2018 Balance Sheet Information: CSX accounts payable to Conrail $ 213 $ 153 Promissory notes payable to Conrail subsidiary 2.89% CSX promissory note due October 2044 73 73 2.89% CSXT promissory note due October 2044 151 151 December December Balance sheet information: 2019 2018 CSX payable to TTX $ 34 $ 36

Other Comprehensive Income _ _2

Other Comprehensive Income / (Loss) (Tables)	12 Months Ended
Other Comprehensive Income / (Loss) (Tables)	Dec. 31, 2019
Equity [Abstract]
Schedule of Changes in the AOCI Balance by Component	Changes in the AOCI balance by component are shown in the following table. Amounts reclassified in pension and other post-employment benefits to net earnings relate to the amortization of actuarial losses and are included in other income-net on the consolidated income statements. See Note 9. Employee Benefit Plans for further information. Other primarily represents CSX's share of AOCI of equity method investees. Amounts reclassified in other to net earnings are included in equity earnings of affiliates on the consolidated income statements. Pension and Other Post-Employment Benefits Other Accumulated Other Comprehensive Income (Loss) (Dollars in millions) Balance December 30, 2016 - Net of Tax $ (580 ) $ (60 ) $ (640 ) Other Comprehensive Income (Loss) Income Before Reclassifications 148 13 161 Amounts Reclassified to Net Earnings 56 2 58 Tax Expense (64 ) (1 ) (65 ) Total Other Comprehensive Income 140 14 154 Balance December 31, 2017 - Net of Tax (440 ) (46 ) (486 ) Other Comprehensive Income (Loss) Reclassification of Stranded Tax Effects (a) (108 ) 1 (107 ) Loss Before Reclassifications (111 ) (8 ) (119 ) Amounts Reclassified to Net Earnings 38 (6 ) 32 Tax Benefit 17 2 19 Total Other Comprehensive Loss (164 ) (11 ) (175 ) Balance December 31, 2018 - Net of Tax (604 ) (57 ) (661 ) Other Comprehensive Income (Loss) Loss Before Reclassifications (43 ) (5 ) (48 ) Amounts Reclassified to Net Earnings 23 8 31 Tax Benefit 5 (2 ) 3 Total Other Comprehensive (Loss) Income (15 ) 1 (14 ) Balance December 31, 2019 - Net of Tax $ (619 ) $ (56 ) $ (675 )

Quarterly Financial Data (Una_2

Quarterly Financial Data (Unaudited) (Tables)	12 Months Ended
Quarterly Financial Data (Unaudited) (Tables)	Dec. 31, 2019
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Data (Unaudited)	Pursuant to Article 3 of the SEC’s Regulation S-X, the following are selected quarterly financial data: Fiscal Year Ended December 2019 Quarters (Dollars in Millions, Except Per Share Amounts) 1st 2nd 3rd 4th Full Year Revenue $ 3,013 $ 3,061 $ 2,978 $ 2,885 $ 11,937 Operating Income 1,219 1,305 1,287 1,154 4,965 Net Earnings 834 870 856 771 3,331 Earnings Per Share, Basic $ 1.02 $ 1.08 $ 1.08 $ 0.99 $ 4.18 Earnings Per Share, Assuming Dilution 1.02 1.08 1.08 0.99 4.17 Fiscal Year Ended December 2018 Revenue $ 2,876 $ 3,102 $ 3,129 $ 3,143 $ 12,250 Operating Income 1,044 1,283 1,293 1,249 4,869 Net Earnings 695 877 894 843 3,309 Earnings Per Share, Basic $ 0.78 $ 1.02 $ 1.05 $ 1.02 $ 3.86 Earnings Per Share, Assuming Dilution 0.78 1.01 1.05 1.01 3.84

Summarized Consolidating Fina_2

Summarized Consolidating Financial Data (Tables)	12 Months Ended
Summarized Consolidating Financial Data (Tables)	Dec. 31, 2019
Condensed Financial Information Disclosure [Abstract]
Consolidating Income Statements	Consolidating Income Statements (Dollars in Millions) Fiscal Year Ended December 2019 CSX Corporation CSX Transportation Eliminations and Other CSX Consolidated Revenue $ — $ 11,856 $ 81 $ 11,937 Expense (549 ) 7,688 (167 ) 6,972 Operating Income 549 4,168 248 4,965 Equity in Earnings of Subsidiaries 3,505 — (3,505 ) — Interest Expense (878 ) (42 ) 183 (737 ) Other Income - Net 25 207 (144 ) 88 Earnings Before Income Taxes 3,201 4,333 (3,218 ) 4,316 Income Tax Benefit (Expense) 130 (1,009 ) (106 ) (985 ) Net Earnings $ 3,331 $ 3,324 $ (3,324 ) $ 3,331 Total Comprehensive Earnings $ 3,317 $ 3,306 $ (3,306 ) $ 3,317 Fiscal Year Ended December 2018 Revenue $ — $ 12,174 $ 76 $ 12,250 Expense (344 ) 7,868 (143 ) 7,381 Operating Income 344 4,306 219 4,869 Equity in Earnings of Subsidiaries 3,580 — (3,580 ) — Interest Expense (742 ) (39 ) 142 (639 ) Other Income - Net 24 152 (102 ) 74 Earnings Before Income Taxes 3,206 4,419 (3,321 ) 4,304 Income Tax Benefit (Expense) 103 (1,036 ) (62 ) (995 ) Net Earnings $ 3,309 $ 3,383 $ (3,383 ) $ 3,309 Total Comprehensive Earnings $ 3,134 $ 3,441 $ (3,441 ) $ 3,134 Fiscal Year Ended December 2017 Revenue $ — $ 11,334 $ 74 $ 11,408 Expense (158 ) 8,009 (163 ) 7,688 Operating Income 158 3,325 237 3,720 Equity in Earnings of Subsidiaries 5,810 — (5,810 ) — Interest Expense (582 ) (29 ) 65 (546 ) Other Income - Net 7 (19 ) (20 ) (32 ) Earnings Before Income Taxes 5,393 3,277 (5,528 ) 3,142 Income Tax Benefit 78 2,247 4 2,329 Net Earnings $ 5,471 $ 5,524 $ (5,524 ) $ 5,471 Total Comprehensive Earnings $ 5,625 $ 5,538 $ (5,538 ) $ 5,625
Consolidating Balance Sheets	Consolidating Balance Sheets (Dollars in Millions) As of December 31, 2019 CSX Corporation CSX Transportation Eliminations and Other CSX ASSETS Current Assets: Cash and Cash Equivalents $ 814 $ 136 $ 8 $ 958 Short-term Investments 989 — 7 996 Accounts Receivable - Net 4 969 13 986 Receivable from Affiliates 1,054 7,405 (8,459 ) — Materials and Supplies — 261 — 261 Other Current Assets 26 30 21 77 Total Current Assets 2,887 8,801 (8,410 ) 3,278 Properties 1 42,110 2,989 45,100 Accumulated Depreciation (1 ) (11,199 ) (1,732 ) (12,932 ) Properties - Net — 30,911 1,257 32,168 Investments in Conrail — — 982 982 Affiliates and Other Companies (39 ) 923 13 897 Investment in Consolidated Subsidiaries 34,528 — (34,528 ) — Right of Use Lease Asset — 514 18 532 Other Long-term Assets 3 629 (232 ) 400 Total Assets $ 37,379 $ 41,778 $ (40,900 ) $ 38,257 LIABILITIES AND SHAREHOLDERS' EQUITY Current Liabilities: Accounts Payable $ 153 $ 830 $ 60 $ 1,043 Labor and Fringe Benefits Payable 38 386 65 489 Payable to Affiliates 9,552 574 (10,126 ) — Casualty, Environmental and Other Reserves — 87 13 100 Current Maturities of Long-term Debt — 245 — 245 Income and Other Taxes Payable (286 ) 340 15 69 Other Current Liabilities — 192 13 205 Total Current Liabilities 9,457 2,654 (9,960 ) 2,151 Casualty, Environmental and Other Reserves — 169 36 205 Long-term Debt 15,534 459 — 15,993 Deferred Income Taxes - Net (152 ) 6,827 286 6,961 Long-term Lease Liability — 481 12 493 Other Long-term Liabilities 692 215 (316 ) 591 Total Liabilities 25,531 10,805 (9,942 ) 26,394 Shareholders' Equity: Common Stock, $1 Par Value 773 181 (181 ) 773 Other Capital 346 5,096 (5,096 ) 346 Retained Earnings 11,404 25,646 (25,646 ) 11,404 Accumulated Other Comprehensive Loss (675 ) 35 (35 ) (675 ) Noncontrolling Minority Interest — 15 — 15 Total Shareholders' Equity 11,848 30,973 (30,958 ) 11,863 Total Liabilities and Shareholders' Equity $ 37,379 $ 41,778 $ (40,900 ) $ 38,257 NOTE 18. Summarized Consolidating Financial Data, continued Consolidating Balance Sheets (Dollars in Millions) As of December 31, 2018 CSX Corporation CSX Transportation Eliminations and Other CSX ASSETS Current Assets Cash and Cash Equivalents $ 716 $ 130 $ 12 $ 858 Short-term Investments 250 — 3 253 Accounts Receivable - Net 1 1,003 6 1,010 Receivable from Affiliates 1,020 5,214 (6,234 ) — Materials and Supplies — 263 — 263 Other Current Assets 63 104 14 181 Total Current Assets 2,050 6,714 (6,199 ) 2,565 Properties 1 41,897 2,907 44,805 Accumulated Depreciation (1 ) (11,194 ) (1,612 ) (12,807 ) Properties - Net — 30,703 1,295 31,998 Investments in Conrail — — 943 943 Affiliates and Other Companies (39 ) 859 16 836 Investment in Consolidated Subsidiaries 32,033 — (32,033 ) — Other Long-term Assets 2 598 (213 ) 387 Total Assets $ 34,046 $ 38,874 $ (36,191 ) $ 36,729 LIABILITIES AND SHAREHOLDERS' EQUITY Current Liabilities Accounts Payable $ 132 $ 763 $ 54 $ 949 Labor and Fringe Benefits Payable 41 440 69 550 Payable to Affiliates 6,973 633 (7,606 ) — Casualty, Environmental and Other Reserves — 99 14 113 Current Maturities of Long-term Debt — 18 — 18 Income and Other Taxes Payable (290 ) 392 4 106 Other Current Liabilities 11 162 6 179 Total Current Liabilities 6,867 2,507 (7,459 ) 1,915 Casualty, Environmental and Other Reserves — 176 35 211 Long-term Debt 14,029 710 — 14,739 Deferred Income Taxes - Net (134 ) 6,601 223 6,690 Other Long-term Liabilities 721 211 (338 ) 594 Total Liabilities 21,483 10,205 (7,539 ) 24,149 Shareholders' Equity Common Stock, $1 Par Value 818 181 (181 ) 818 Other Capital 249 5,096 (5,096 ) 249 Retained Earnings 12,157 23,322 (23,322 ) 12,157 Accumulated Other Comprehensive Loss (661 ) 53 (53 ) (661 ) Noncontrolling Minority Interest — 17 — 17 Total Shareholders' Equity 12,563 28,669 (28,652 ) 12,580 Total Liabilities and Shareholders' Equity $ 34,046 $ 38,874 $ (36,191 ) $ 36,729
Consolidating Cash Flow Statements	Consolidating Cash Flow Statements (Dollars in Millions) Fiscal Year Ended December 2019 CSX Corporation CSX Transportation Eliminations and Other CSX Operating Activities Net Cash Provided by (Used in) Operating Activities $ 3,440 $ 2,272 $ (862 ) $ 4,850 Investing Activities Property Additions — (1,506 ) (151 ) (1,657 ) Purchases of Short-term Investments (2,838 ) — — (2,838 ) Proceeds from Sales of Short-term Investments 2,105 — 3 2,108 Proceeds from Property Dispositions — 254 — 254 Other Investing Activities 15 10 6 31 Net Cash Used in Investing Activities (718 ) (1,242 ) (142 ) (2,102 ) Financing Activities Long-term Debt Issued 2,000 — — 2,000 Long-term Debt Repaid (500 ) (18 ) — (518 ) Dividends Paid (763 ) (1,000 ) 1,000 (763 ) Shares Repurchased (3,373 ) — — (3,373 ) Other Financing Activities 12 (6 ) — 6 Net Cash (Used in) Provided by Financing Activities (2,624 ) (1,024 ) 1,000 (2,648 ) Net Increase in Cash and Cash Equivalents 98 6 (4 ) 100 Cash and Cash Equivalents at Beginning of Period 716 130 12 858 Cash and Cash Equivalents at End of Period $ 814 $ 136 $ 8 $ 958 NOTE 18. Summarized Consolidating Financial Data, continued Consolidating Cash Flow Statements (Dollars in Millions) Fiscal Year Ended December 2018 CSX Corporation CSX Transportation Eliminations and Other CSX Operating Activities Net Cash Provided by (Used in) Operating Activities $ 3,182 $ 1,657 $ (198 ) $ 4,641 Investing Activities Property Additions — (1,580 ) (165 ) (1,745 ) Purchases of Short-term Investments (734 ) — (2 ) (736 ) Proceeds from Sales of Short-term Investments 485 — 20 505 Proceeds from Property Dispositions — 319 — 319 Other Investing Activities (4 ) 638 (661 ) (27 ) Net Cash Used in Investing Activities (253 ) (623 ) (808 ) (1,684 ) Financing Activities Long-term Debt Issued 3,000 — — 3,000 Long-term Debt Repaid — (19 ) — (19 ) Dividends Paid (751 ) (1,000 ) 1,000 (751 ) Shares Repurchased (4,671 ) — — (4,671 ) Other Financing Activities (65 ) (6 ) 12 (59 ) Net Cash (Used in) Provided by Financing Activities (2,487 ) (1,025 ) 1,012 (2,500 ) Net Decrease in Cash and Cash Equivalents 442 9 6 457 Cash and Cash Equivalents at Beginning of Period 274 121 6 401 Cash and Cash Equivalents at End of Period $ 716 $ 130 $ 12 $ 858 NOTE 18. Summarized Consolidating Financial Data, continued Consolidating Cash Flow Statements (Dollars in Millions) Fiscal Year Ended December 2017 CSX Corporation CSX Transportation Eliminations and Other CSX Operating Activities Net Cash Provided by (Used in) Operating Activities $ 1,719 $ 2,112 $ (359 ) $ 3,472 Investing Activities Property Additions — (1,848 ) (192 ) (2,040 ) Purchases of Short-term Investments (774 ) — (8 ) (782 ) Proceeds from Sales of Short-term Investments 1,190 — 3 1,193 Proceeds from Property Dispositions — 97 — 97 Other Investing Activities (2 ) 94 (55 ) 37 Net Cash Provided by (Used in) Investing Activities 414 (1,657 ) (252 ) (1,495 ) Financing Activities Long-term Debt Issued 850 — — 850 Long-term Debt Repaid (313 ) (20 ) — (333 ) Dividends Paid (708 ) (600 ) 600 (708 ) Shares Repurchased (1,970 ) — — (1,970 ) Other Financing Activities (23 ) 5 — (18 ) Net Cash (Used in) Provided by Financing Activities (2,164 ) (615 ) 600 (2,179 ) Net (Decrease) Increase in Cash and Cash Equivalents (31 ) (160 ) (11 ) (202 ) Cash and Cash Equivalents at Beginning of Period 305 281 17 603 Cash and Cash Equivalents at End of Period $ 274 $ 121 $ 6 $ 401

Nature of Operations and Sign_4

Nature of Operations and Significant Accounting Policies - Narrative (Details) mi in Thousands, carload in Thousands, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019USD ($)employeerailroadport_terminalstateterminalmi	Sep. 30, 2019USD ($)	Jun. 30, 2019USD ($)	Mar. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Sep. 30, 2018USD ($)	Jun. 30, 2018USD ($)	Mar. 31, 2018USD ($)	Dec. 31, 2019USD ($)employeerailroadcarloadport_terminalstateterminalline_of_businessmi	Dec. 31, 2018USD ($)	Dec. 31, 2017USD ($)employee	Jan. 01, 2019USD ($)
Revenue from External Customer [Line Items]
Number of rail route miles \| mi	20								20
Rail network states number \| state	23								23
Number of ocean, river and lake ports serviced (more than) \| port_terminal	70								70
Number of short-line and regional railroads served (more than) \| railroad	230								230
Revenue	$ 2,885	$ 2,978	$ 3,061	$ 3,013	$ 3,143	$ 3,129	$ 3,102	$ 2,876	$ 11,937	$ 12,250	$ 11,408
Number of primary lines of business \| line_of_business									3
Number of employees \| employee	21,000								21,000
Number of union employees \| employee									17,000
Cost method, maximum percentage									20.00%
Operating lease right-of-use asset	$ 532				$ 0				$ 532	0
Operating lease liabilities	$ 550								550
Expenses related to management workforce reduction and other restructuring charges									$ 0	$ 0	$ 325
Accounting Standards Update 2016-02
Revenue from External Customer [Line Items]
Operating lease right-of-use asset												$ 534
Operating lease liabilities												$ 534
Management streamlining
Revenue from External Customer [Line Items]
Workforce reduction \| employee											950
Expenses related to management workforce reduction and other restructuring charges											$ 325
Merchandise business
Revenue from External Customer [Line Items]
Number of carloads \| carload									2,700
Percentage of total volume									43.00%
Percentage of total revenue									64.00%
Coal business
Revenue from External Customer [Line Items]
Number of carloads \| carload									843
Percentage of total volume									14.00%
Percentage of total revenue									17.00%
Intermodal business
Revenue from External Customer [Line Items]
Number of carloads \| carload									2,700
Percentage of total volume									43.00%
Percentage of total revenue									15.00%
Number of terminals \| terminal	30								30
Other business
Revenue from External Customer [Line Items]
Percentage of total revenue									4.00%

Nature of Operations and Sign_5

Nature of Operations and Significant Accounting Policies - Restructuring Charges (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restructuring Cost and Reserve [Line Items]
Operating Restructuring Charge	$ 0	$ 0	$ 240
Non-Operating Restructuring Charge	$ 0	$ 0	85
Management streamlining
Restructuring Cost and Reserve [Line Items]
Operating Restructuring Charge			240
Non-Operating Restructuring Charge			85
Management streamlining \| Subtotal Management Workforce Reduction
Restructuring Cost and Reserve [Line Items]
Operating Restructuring Charge			121
Non-Operating Restructuring Charge			73
Management streamlining \| Severance and Pension
Restructuring Cost and Reserve [Line Items]
Operating Restructuring Charge			98
Non-Operating Restructuring Charge			56
Management streamlining \| Other Post-Retirement Benefits Curtailment
Restructuring Cost and Reserve [Line Items]
Operating Restructuring Charge			0
Non-Operating Restructuring Charge			17
Management streamlining \| Employee Equity Awards Proration and Other
Restructuring Cost and Reserve [Line Items]
Operating Restructuring Charge			23
Non-Operating Restructuring Charge			0
Management streamlining \| Reimbursement Arrangements
Restructuring Cost and Reserve [Line Items]
Operating Restructuring Charge			84
Non-Operating Restructuring Charge			0
Management streamlining \| Executive Equity Awards Proration
Restructuring Cost and Reserve [Line Items]
Operating Restructuring Charge			24
Non-Operating Restructuring Charge			0
Management streamlining \| Pension Settlement Charge
Restructuring Cost and Reserve [Line Items]
Operating Restructuring Charge			0
Non-Operating Restructuring Charge			12
Management streamlining \| Advisory Fees Related to Shareholder Matters
Restructuring Cost and Reserve [Line Items]
Operating Restructuring Charge			11
Non-Operating Restructuring Charge			$ 0

Earnings Per Share - Computatio

Earnings Per Share - Computation of Basic and Diluted Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Numerator:
Net Earnings	$ 771	$ 856	$ 870	$ 834	$ 843	$ 894	$ 877	$ 695	$ 3,331	$ 3,309	$ 5,471
Dividend Equivalents on Restricted Stock									0	(1)	(1)
Net Earnings, Attributable to Common Shareholders									$ 3,331	$ 3,308	$ 5,470
Denominator:
Average Common Shares Outstanding (in shares)									796	857	911
Other Potentially Dilutive Common Shares (in shares)									2	4	3
Average Common Shares Outstanding, Assuming Dilution (in shares)									798	861	914
Earnings Per Share, Basic (in dollars per share)	$ 0.99	$ 1.08	$ 1.08	$ 1.02	$ 1.02	$ 1.05	$ 1.02	$ 0.78	$ 4.18	$ 3.86	$ 6.01
Net Earnings Per Share, Assuming Dilution (in dollars per share)	$ 0.99	$ 1.08	$ 1.08	$ 1.02	$ 1.01	$ 1.05	$ 1.01	$ 0.78	$ 4.17	$ 3.84	$ 5.99

Earnings Per Share - Narrative

Earnings Per Share - Narrative (Details) shares in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)shares	Dec. 31, 2018USD ($)agreementshares	Dec. 31, 2017USD ($)shares	Sep. 30, 2019shares	Aug. 31, 2019USD ($)	Jan. 31, 2019USD ($)	Feb. 28, 2018USD ($)	Oct. 31, 2017USD ($)	Jul. 31, 2017USD ($)	Apr. 30, 2017USD ($)	Apr. 30, 2015USD ($)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of shares repurchased (in shares) \| shares	48,000	72,000	39,000
Amount of shares repurchased	$ 3,373,000,000	$ 4,671,000,000	$ 1,970,000,000
Share Repurchase Program January 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Share repurchase program authorized amount						$ 5,000,000,000
Share repurchase program, remaining amount						$ 1,800,000,000
Share Repurchase Program January 2019 \| 2019
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Accelerated share repurchase program payment					$ 250,000,000
Accelerated share repurchase program initial shares received (in shares) \| shares				4,000
Share Repurchase Program October 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Share repurchase program authorized amount							$ 5,000,000,000	$ 1,500,000,000
Share Repurchase Program October 2017 \| 2018
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of shares repurchased (in shares) \| shares		22,000
Accelerated share repurchase program payment		$ 1,500,000,000
Number of accelerated share repurchase agreements entered into by the Company \| agreement		4
Share Repurchase Program April 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Share repurchase program authorized amount									$ 1,500,000,000	$ 1,000,000,000
Share Repurchase Program April 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Share repurchase program authorized amount											$ 2,000,000,000
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares) \| shares	877	479	7,600

Earnings Per Share - Share Repu

Earnings Per Share - Share Repurchase Activity (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings Per Share [Abstract]
Stock repurchased (in shares)	48	72	39
Cost of Shares	$ 3,373	$ 4,671	$ 1,970
Average Price Paid per Share (in dollars per share)	$ 70.54	$ 64.64	$ 50.80

Shareholders' Equity (Details)

Shareholders' Equity (Details) - $ / shares	12 Months Ended
Shareholders' Equity (Details) - $ / shares	Dec. 31, 2019	Dec. 31, 2018
Class of Stock [Line Items]
Common stock par value (in dollars per share)	$ 1	$ 1
Common Stock
Class of Stock [Line Items]
Common Shares Authorized (in shares)	1,800,000,000
Common Shares Issued (in shares)	773,000,000
Common Shares Outstanding (in shares)	773,000,000
Common stock, number of votes per share	$ 1
Preferred Stock
Class of Stock [Line Items]
Preferred Shares Authorized (in shares)	25,000,000
Preferred Shares Issued (in shares)	0
Preferred Shares Outstanding (in shares)	0

Stock Plans and Share-Based C_3

Stock Plans and Share-Based Compensation - Share-Based Compensation and Related Income Tax Benefit (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	$ 74	$ 51	$ 89
Income Tax Benefit	43	26	42
Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	42	28	49
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	18	13	22
Restricted Stock Units and Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	8	6	15
Stock Awards for Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	2	2	3
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	$ 4	$ 2	$ 0

Stock Plans and Share-Based C_4

Stock Plans and Share-Based Compensation - Narrative (Details)	1 Months Ended		8 Months Ended	12 Months Ended
	Dec. 31, 2017shares	Mar. 31, 2017$ / sharesshares	Dec. 31, 2018	Dec. 31, 2019USD ($)plan$ / sharesshares	Dec. 31, 2018$ / shares	Dec. 31, 2017USD ($)employee$ / shares	May 31, 2018USD ($)shares
Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted (in shares) \| shares		9,000,000
Fair value of stock options granted (in dollars per share) \| $ / shares		$ 12.88
Options forfeited (in shares) \| shares	9,000,000
Non-management Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual retainer to be paid to non-management directors, common stock option \| $				$ 162,500
Chairman
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual grant of common stock amount \| $				250,000
Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost \| $				$ 23,000,000
Expected weighted average period of recognition for unrecognized compensation cost (in years)				2 years
Expected life (in years)				2 years 9 months 18 days	2 years 10 months 24 days
Restricted Stock Units and Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost \| $				$ 8,000,000
Expected weighted average period of recognition for unrecognized compensation cost (in years)				2 years
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award performance period				3 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award performance period				5 years
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost \| $				$ 15,000,000
Expected weighted average period of recognition for unrecognized compensation cost (in years)				2 years
Expected life (in years)				6 years 1 month 6 days	6 years 6 months	6 years 3 months 18 days
Stock options granted (in shares) \| shares				1,187,000
Fair value of stock options granted (in dollars per share) \| $ / shares				$ 17.87	$ 14.65	$ 12.84
Stock Options \| Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award term		10 years
LITP \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout range (as a percent)				0.00%
LITP \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout range (as a percent)				200.00%
LITP \| Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance unit equivalent of CSX stock (in shares) \| shares				1
Number of plans \| plan				3
LITP \| Restricted Stock Units and Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance unit equivalent of CSX stock (in shares) \| shares				1
LITP \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance unit equivalent of CSX stock (in shares) \| shares				1
LITP \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award term				10 years
LITP \| Stock Options \| Vesting on anniversary of the grant date (graded period)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award performance period				3 years
LITP \| Stock Options \| Vesting after the grant date (cliff period)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award performance period				3 years	3 years	3 years
2017-2019 LTIP \| Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award performance period				3 years
Cumulative payout period				3 years
Percentage payout on operating ratio				50.00%
Percentage payout on average return on assets				50.00%
2017-2019 LTIP \| Performance Units \| Certain Executive Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of payout subject to adjustment				30.00%
2018-2020 LTIP \| Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award performance period				3 years
Percentage payout on operating ratio				50.00%
Percentage payout on average return on assets				50.00%
2018-2020 LTIP \| Performance Units \| Minimum \| Certain Executive Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of payout subject to adjustment				25.00%
2018-2020 LTIP \| Performance Units \| Maximum \| Certain Executive Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of payout subject to adjustment				200.00%
2019-2021 LTIP \| Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award performance period				3 years
Percentage payout on operating ratio				50.00%
Percentage payout on average return on assets				50.00%
2019-2021 LTIP \| Performance Units \| Minimum \| Certain Executive Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of payout subject to adjustment				50.00%
2019-2021 LTIP \| Performance Units \| Maximum \| Certain Executive Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of payout subject to adjustment				250.00%
Equity Award Modifications
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of employees impacted \| employee						75
Share-based compensation expense revaluation of awards \| $						$ 39,000,000
Non-management Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual retainer to be paid to non-management directors, cash option \| $				$ 112,500
ESPP \| Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of registered shares of common stock that my be issued pursuant to plan (in shares) \| shares							4,000,000
Employee contribution percentage, minimum							1.00%
Employee contribution percentage, maximum							10.00%
Maximum value of stocks purchased by employee, after tax \| $							$ 25,000
Percentage of share closing market price			85.00%
Share offering period			6 months
Number of shares issued under the plan (in shares) \| shares				250,000

Stock Plans and Share-Based C_5

Stock Plans and Share-Based Compensation - Assumptions Used to Estimate Fair Value of Performance Units (Details) - Performance Units	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual dividend yield	1.40%	1.60%
Risk-free interest rate	2.40%	2.30%
Annualized volatility	27.40%	29.10%
Expected life (in years)	2 years 9 months 18 days	2 years 10 months 24 days

Stock Plans and Share-Based C_6

Stock Plans and Share-Based Compensation - Performance Unit Grant and Vesting Information (Details) - Performance Units - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value (in dollars per share)	$ 66.18	$ 55.57	$ 49.50
Fair value of units vested in fiscal year ending (in millions)	$ 17	$ 14	$ 26

Stock Plans and Share-Based C_7

Stock Plans and Share-Based Compensation - Performance Unit Activity Related to Outstanding Long-term Incentive Plans and Corresponding Fair Value (Details) - Performance Units shares in Thousands	12 Months Ended
	Dec. 31, 2019$ / sharesshares
Weighted-Average Fair Value at Grant Date
Unvested, Weighted-Average Fair Value at Grant Date, beginning of period (in dollars per share)	$ 55.57
Unvested, Weighted-Average Fair Value at Grant Date, end of period (in dollars per share)	$ 66.18
Long-term Incentive Plans
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Unvested, Units Outstanding, beginning balance (in shares) \| shares	722
Granted (in shares) \| shares	337
Forfeited (in shares) \| shares	(75)
Vested (in shares) \| shares	(341)
Unvested, Units Outstanding, ending balance (in shares) \| shares	643
Weighted-Average Fair Value at Grant Date
Unvested, Weighted-Average Fair Value at Grant Date, beginning of period (in dollars per share)	$ 52.58
Granted (in dollars per share)	66.18
Forfeited (in dollars per share)	57.20
Vested (in dollars per share)	49.52
Unvested, Weighted-Average Fair Value at Grant Date, end of period (in dollars per share)	$ 60.58

Stock Plans and Share-Based C_8

Stock Plans and Share-Based Compensation - Assumptions and Inputs Used to Estimate Fair Value of Stock Options (Details) - Stock Options - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value (in dollars per share)	$ 17.87	$ 14.65	$ 12.84
Annual dividend yield	1.30%	1.50%	1.50%
Risk-free interest rate	2.40%	2.60%	2.20%
Annualized volatility	25.70%	27.00%	27.10%
Expected life (in years)	6 years 1 month 6 days	6 years 6 months	6 years 3 months 18 days
Weighted-average grant-date market price of CSX stock (strike price) (in dollars per share)	$ 70.01	$ 54.19	$ 49.63

Stock Plans and Share-Based C_9

Stock Plans and Share-Based Compensation - Stock Option Activity (Details) - Stock Options $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward]
Outstanding beginning of period (in shares) \| shares	4,673
Granted (in shares) \| shares	1,187
Forfeited (in shares) \| shares	(212)
Exercised (in shares) \| shares	(1,853)
Outstanding end of period (in shares) \| shares	3,795
Exercisable (in shares) \| shares	1,026
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Outstanding at beginning of period (in dollars per share) \| $ / shares	$ 34.89
Granted (in dollars per share) \| $ / shares	70.01
Forfeited (in dollars per share) \| $ / shares	55.35
Exercised (in dollars per share) \| $ / shares	24.48
Outstanding at end of period (in dollars per share) \| $ / shares	49.78
Exercisable (in dollars per share) \| $ / shares	$ 24.60
Outstanding, weighted-average remaining contractual life (in years)	7 years 6 months
Exercisable, weighted-average remaining contractual life (in years)	6 years
Outstanding, aggregate intrinsic value \| $	$ 87
Exercisable, aggregate intrinsic value \| $	$ 49

Stock Plans and Share-Based _10

Stock Plans and Share-Based Compensation - Intrinsic Value and Cash Received on Exercises (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)
Share-based Payment Arrangement [Abstract]
Intrinsic value of stock options exercised	$ 87
Cash received from option exercises	$ 45

Stock Plans and Share-Based _11

Stock Plans and Share-Based Compensation - Restricted Stock Grant and Vesting Information (Details) - Restricted Stock Units and Awards - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value (in dollars per share)	$ 69.19	$ 62.60	$ 48.35
Fair value of units vested in fiscal year ending (in millions)	$ 7	$ 9	$ 8

Stock Plans and Share-Based _12

Stock Plans and Share-Based Compensation - Outstanding Restricted Stock Units and Award (Details) - Restricted Stock Units and Awards shares in Thousands	12 Months Ended
	Dec. 31, 2019$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Unvested, Units Outstanding, beginning balance (in shares) \| shares	684
Granted (in shares) \| shares	88
Forfeited (in shares) \| shares	(30)
Vested (in shares) \| shares	(315)
Unvested, Units Outstanding, ending balance (in shares) \| shares	427
Weighted-Average Fair Value at Grant Date
Unvested, Weighted-Average Fair Value at Grant Date, beginning of period (in dollars per share) \| $ / shares	$ 39.30
Granted (in dollars per share) \| $ / shares	69.19
Forfeited (in dollars per share) \| $ / shares	53.28
Vested (in dollars per share) \| $ / shares	24.21
Unvested, Weighted-Average Fair Value at Grant Date, end of period (in dollars per share) \| $ / shares	$ 57.29

Casualty, Environmental and O_3

Casualty, Environmental and Other Reserves - Schedule of Claims Activity (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Loss Contingency Accrual [Roll Forward]
Balance at beginning of period	$ 324	$ 374	$ 374
Charged to Expense	107	72	114
Payments	(126)	(122)	(114)
Balance end of period	305	324	374
Casualty Reserves
Loss Contingency Accrual [Roll Forward]
Balance at beginning of period	199	228	229
Charged to Expense	56	21	43
Payments	(68)	(50)	(44)
Balance end of period	187	199	228
Environmental Reserves
Loss Contingency Accrual [Roll Forward]
Balance at beginning of period	80	90	95
Charged to Expense	17	10	26
Payments	(23)	(20)	(31)
Balance end of period	74	80	90
Other Reserves
Loss Contingency Accrual [Roll Forward]
Balance at beginning of period	45	56	50
Charged to Expense	34	41	45
Payments	(35)	(52)	(39)
Balance end of period	$ 44	$ 45	$ 56

Casualty, Environmental and O_4

Casualty, Environmental and Other Reserves - Balance Sheet Presentation (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 30, 2016
Contingencies [Line Items]
Current	$ 100	$ 113
Long-term	205	211
Total	305	324	$ 374	$ 374
Casualty
Contingencies [Line Items]
Current	48	50
Long-term	139	149
Total	187	199	228	229
Personal Injury
Contingencies [Line Items]
Current	42	40
Long-term	87	103
Total	129	143
Occupational
Contingencies [Line Items]
Current	6	10
Long-term	52	46
Total	58	56
Environmental
Contingencies [Line Items]
Current	31	39
Long-term	43	41
Total	74	80	90	95
Other
Contingencies [Line Items]
Current	21	24
Long-term	23	21
Total	$ 44	$ 45	$ 56	$ 50

Casualty, Environmental and O_5

Casualty, Environmental and Other Reserves - Narrative (Details) $ / shares in Units, $ in Millions	Jun. 01, 2018USD ($)	Dec. 31, 2019USD ($)claimsite$ / shares	Sep. 30, 2019$ / shares	Jun. 30, 2019$ / shares	Mar. 31, 2019$ / shares	Dec. 31, 2018USD ($)$ / shares	Sep. 30, 2018$ / shares	Jun. 30, 2018$ / shares	Mar. 31, 2018$ / shares	Dec. 31, 2019USD ($)claimsite$ / shares	Dec. 31, 2018USD ($)$ / shares	Dec. 31, 2017USD ($)$ / shares	Dec. 30, 2016USD ($)
Loss Contingencies [Line Items]
Reserves		$ 305				$ 324				$ 305	$ 324	$ 374	$ 374
Earnings per share impact (in dollars per share) \| $ / shares		$ 0.99	$ 1.08	$ 1.08	$ 1.02	$ 1.02	$ 1.05	$ 1.02	$ 0.78	$ 4.18	$ 3.86	$ 6.01
Casualty
Loss Contingencies [Line Items]
Reserves		$ 187				$ 199				$ 187	$ 199	$ 228	229
Individual claims expected to exceed self-insured retention amount \| claim		0								0
Casualty \| Minimum
Loss Contingencies [Line Items]
Self-insured retention amount per injury	$ 50
Casualty \| Maximum
Loss Contingencies [Line Items]
Self-insured retention amount per injury	$ 75
Personal Injury
Loss Contingencies [Line Items]
Reserves		$ 129				143				$ 129	143
Environmental
Loss Contingencies [Line Items]
Reserves		$ 74				80				$ 74	80	90	95
Environmental impaired sites \| site		220								220
Other
Loss Contingencies [Line Items]
Reserves		$ 44				$ 45				$ 44	$ 45	$ 56	$ 50

Properties - Schedule of Net Pr

Properties - Schedule of Net Properties (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 45,100	$ 44,805
Accumulated Depreciation	(12,932)	(12,807)
Properties - Net (Note 6)	32,168	31,998
Total Road
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	32,125	31,411
Accumulated Depreciation	(8,618)	(8,323)
Properties - Net (Note 6)	23,507	23,088
Rail and Other Track Material
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	8,194	7,964
Accumulated Depreciation	(1,719)	(1,698)
Properties - Net (Note 6)	$ 6,475	$ 6,266
Annual Depreciation Rate	2.50%	2.50%
Estimated useful life (Avg. Years)	40 years	40 years
Ties
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 6,041	$ 5,860
Accumulated Depreciation	(1,666)	(1,557)
Properties - Net (Note 6)	$ 4,375	$ 4,303
Annual Depreciation Rate	3.70%	3.70%
Estimated useful life (Avg. Years)	27 years	27 years
Grading
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 2,763	$ 2,757
Accumulated Depreciation	(595)	(572)
Properties - Net (Note 6)	$ 2,168	$ 2,185
Annual Depreciation Rate	1.40%	1.40%
Estimated useful life (Avg. Years)	72 years	72 years
Ballast
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 3,156	$ 3,076
Accumulated Depreciation	(1,013)	(971)
Properties - Net (Note 6)	$ 2,143	$ 2,105
Annual Depreciation Rate	2.70%	2.70%
Estimated useful life (Avg. Years)	37 years	37 years
Bridges, Trestles, and Culverts
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 2,529	$ 2,506
Accumulated Depreciation	(334)	(382)
Properties - Net (Note 6)	$ 2,195	$ 2,124
Annual Depreciation Rate	1.60%	1.60%
Estimated useful life (Avg. Years)	61 years	61 years
Signals and Interlockers
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 3,077	$ 2,975
Accumulated Depreciation	(819)	(693)
Properties - Net (Note 6)	$ 2,258	$ 2,282
Annual Depreciation Rate	4.00%	4.00%
Estimated useful life (Avg. Years)	25 years	25 years
Buildings
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 1,335	$ 1,318
Accumulated Depreciation	(492)	(486)
Properties - Net (Note 6)	$ 843	$ 832
Annual Depreciation Rate	2.50%	2.50%
Estimated useful life (Avg. Years)	40 years	40 years
Other
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 5,030	$ 4,955
Accumulated Depreciation	(1,980)	(1,964)
Properties - Net (Note 6)	$ 3,050	$ 2,991
Annual Depreciation Rate	4.20%	4.20%
Estimated useful life (Avg. Years)	24 years	24 years
Total Equipment
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 10,708	$ 11,092
Accumulated Depreciation	(4,314)	(4,484)
Properties - Net (Note 6)	6,394	6,608
Locomotive
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	5,320	5,661
Accumulated Depreciation	(2,020)	(2,266)
Properties - Net (Note 6)	$ 3,300	$ 3,395
Annual Depreciation Rate	3.60%	3.50%
Estimated useful life (Avg. Years)	27 years	29 years
Freight Cars
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 2,964	$ 3,093
Accumulated Depreciation	(880)	(882)
Properties - Net (Note 6)	$ 2,084	$ 2,211
Annual Depreciation Rate	2.90%	2.90%
Estimated useful life (Avg. Years)	35 years	35 years
Work Equipment and Other
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 2,424	$ 2,338
Accumulated Depreciation	(1,414)	(1,336)
Properties - Net (Note 6)	$ 1,010	$ 1,002
Annual Depreciation Rate	8.20%	7.40%
Estimated useful life (Avg. Years)	12 years	14 years
Land
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 1,836	$ 1,845
Properties - Net (Note 6)	1,836	1,845
Construction In Progress
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	431	457
Properties - Net (Note 6)	$ 431	$ 457

Properties - Narrative (Details

Properties - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Properties - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Percentage of labor costs relating to the deconstruction of old track		20.00%
Percentage of labor costs relating to the installation of new track		80.00%
Percentage of assets depreciated under the group-life method		87.00%
Total fixed assets		$ 45,100	$ 44,805
Depreciation expense		1,349	1,331	$ 1,315
Gains on sale of properties		151	154	18
Impairment expense		22	24	$ 25
Total Equipment
Property, Plant and Equipment [Line Items]
Total fixed assets		$ 10,708	11,092
Life studies, frequency period		3 years
Total Equipment \| Service Life \| Forecast
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 30
Total Road
Property, Plant and Equipment [Line Items]
Total fixed assets		$ 32,125	$ 31,411
Life studies, frequency period		6 years

Leases - Narrative (Details)

Leases - Narrative (Details) $ in Millions	Jan. 01, 2019USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018mi
Lessee, Lease, Description [Line Items]
Number of miles of land and integral equipment leased \| mi			137
Additional lease term			50 years
Percentage of annual increase in operating lease payments			2.50%
Right-of-use asset recognized as non-cash asset addition	$ 534	$ 51
Cash paid for amounts included in measurement of operating lease liabilities		$ 60
Maximum
Lessee, Lease, Description [Line Items]
Term of lease agreements (up to)		50 years
Maximum \| Other parties
Lessee, Lease, Description [Line Items]
Term of lease agreements (up to)		50 years

Leases - Schedule of Informatio

Leases - Schedule of Information About Company's Operating Leases (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Maturity of Lease Liabilities
2020	$ 58
2021	54
2022	48
2023	39
2024	37
Thereafter	1,208
Total undiscounted operating lease payments	1,444
Less: Imputed interest	(894)
Present value of operating lease liabilities	550
Balance Sheet Classification
Current lease liabilities (recorded in other current liabilities)	57
Long-term lease liabilities	493	$ 0
Total operating lease liabilities	$ 550
Other Information
Weighted-average remaining lease term for operating leases	33 years
Weighted-average discount rate for operating leases	5.00%

Leases - Operating Lease Costs

Leases - Operating Lease Costs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Leases [Abstract]
Rent Expense on Operating Leases	$ 84	$ 66	$ 78

Commitments and Contingencies -

Commitments and Contingencies - Schedule of Number of Locomotives and Payments under Long-term Maintenance Program (Details) $ in Millions	12 Months Ended
	Dec. 31, 2019USD ($)locomotive	Dec. 31, 2018USD ($)locomotive	Dec. 31, 2017USD ($)locomotive
Commitments and Contingencies Disclosure [Abstract]
Amounts Paid \| $	$ 139	$ 170	$ 197
Number of Locomotives \| locomotive	1,897	1,910	2,062

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Annual Payments under Long-term Maintenance Program (Details) $ in Millions	Dec. 31, 2019USD ($)
Unrecorded Unconditional Purchase Obligation [Abstract]
2020	$ 292
2021	197
2022	229
2023	254
2024	290
Thereafter	2,448
Total	3,710
Locomotive Maintenance & Rebuild Payments
Unrecorded Unconditional Purchase Obligation [Abstract]
2020	233
2021	178
2022	211
2023	237
2024	273
Thereafter	2,337
Total	3,469
Other Commitments
Unrecorded Unconditional Purchase Obligation [Abstract]
2020	59
2021	19
2022	18
2023	17
2024	17
Thereafter	111
Total	$ 241

Commitments and Contingencies_3

Commitments and Contingencies - Narrative (Details)	Jun. 01, 2018USD ($)	Jun. 30, 2018defendant	Mar. 31, 2016partymi	May 31, 2007claimentity	Dec. 31, 2019USD ($)mi
Operating Leased Assets [Line Items]
Casualty and catastrophic property deductible					$ 50,000,000
Non-catastrophic property deductible					$ 25,000,000
Fuel Surcharge Antitrust Litigation
Operating Leased Assets [Line Items]
Number of other U.S.-based entities mentioned in class action lawsuit \| entity				3,000,000
Number of consolidated class action lawsuits \| claim				1
Environmental Litigation
Operating Leased Assets [Line Items]
Number of miles pertaining to Passaic River tidal reach required to be studied by EPA \| mi					17
Number of miles under study \| mi			8
Number of parties participating in allocation process to assign responsibility for costs under study \| party			80
Number of defendants \| defendant		110
Minimum \| Pending Litigation
Operating Leased Assets [Line Items]
Range of possible loss from legal proceedings					$ 1,000,000
Maximum \| Pending Litigation
Operating Leased Assets [Line Items]
Range of possible loss from legal proceedings					$ 29,000,000
Casualty Reserves \| Minimum
Operating Leased Assets [Line Items]
Self-insured retention amount per occurrence	$ 50,000,000
Casualty Reserves \| Maximum
Operating Leased Assets [Line Items]
Self-insured retention amount per occurrence	$ 75,000,000

Employee Benefit Plans - Narrat

Employee Benefit Plans - Narrative (Details) - USD ($)	Jan. 20, 2020	Jan. 01, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Increase (decrease) in post-retirement benefit liability				$ (102,000,000)
Employer contributions			$ 0	0	$ 0
Expected future contributions			0
Pension plan assets at fair value			2,825,000,000	2,431,000,000
Special termination benefits					56,000,000
Amount of premium expenses incurred under the plan			26,000,000	30,000,000	40,000,000
Expense associated with savings plans			$ 41,000,000	41,000,000	39,000,000
Equity
Defined Benefit Plan Disclosure [Line Items]
Targeted allocation of total plan assets in domestic equity			37.00%
Targeted allocation of total plan assets in international equity			23.00%
Percentage within which the planned allocation is managed			3.00%
Pension plan assets at fair value			$ 1,770,000,000	1,698,000,000
Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of pension assets			40.00%
Pension plan assets at fair value			$ 818,000,000	704,000,000
Pension and Other Post-Employment Benefits
Defined Benefit Plan Disclosure [Line Items]
Gain (loss) recognized in other comprehensive income				102,000,000
Post-retirement benefits
Defined Benefit Plan Disclosure [Line Items]
Life insurance and contributions to the medical program for eligible retirees will be eliminated (younger than)		65 years
Increase (decrease) in post-retirement benefit liability			0	102,000,000
Pension plan assets at fair value			0	0	0
Special termination benefits			0	0	13,000,000
Curtailment losses					13,000,000
Pre-tax (loss) gain to be amortized			74,000,000
Post-retirement benefits \| Nonqualified Plan
Defined Benefit Plan Disclosure [Line Items]
Employer contributions			26,000,000	30,000,000
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Increase (decrease) in post-retirement benefit liability			0	0
Pension plan assets at fair value			2,825,000,000	2,431,000,000	2,833,000,000
Decrease to pension liabilities					85,000,000
Special termination benefits			0	0	60,000,000
Curtailment losses					4,000,000
Pre-tax (loss) gain to be amortized			(879,000,000)
Pension Plans \| Qualified Plan
Defined Benefit Plan Disclosure [Line Items]
Settlement losses					11,000,000
Pension Plans \| Nonqualified Plan
Defined Benefit Plan Disclosure [Line Items]
Employer contributions			$ 17,000,000	$ 17,000,000
Settlement losses					$ 12,000,000
Subsequent Event \| Plan \| Post-retirement benefits
Defined Benefit Plan Disclosure [Line Items]
Life insurance and contributions to the medical program for eligible retirees will be eliminated (65 or older)	65 years

Employee Benefit Plans - Summar

Employee Benefit Plans - Summary of Participants (Details)	Jan. 01, 2019employee
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Active Employees	3,521
Retirees and Beneficiaries	12,016
Other	4,012
Total	19,549
Post-retirement Medical Plan
Defined Benefit Plan Disclosure [Line Items]
Active Employees	616
Retirees and Beneficiaries	8,393
Other	40
Total	9,049

Employee Benefit Plans - Schedu

Employee Benefit Plans - Schedule of Future Expected Benefit Payments (Details) $ in Millions	Dec. 31, 2019USD ($)
Pension Benefits
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2020	$ 193
2021	188
2022	186
2023	184
2024	182
2025-2029	897
Total	1,830
Post-retirement Benefits
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2020	20
2021	12
2022	10
2023	9
2024	9
2025-2029	34
Total	$ 94

Employee Benefit Plans - Sche_2

Employee Benefit Plans - Schedule of Allocation of Plan Assets (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Amount	$ 2,825	$ 2,431
Percent of Total Assets	100.00%	100.00%
Equity
Defined Benefit Plan Disclosure [Line Items]
Amount	$ 1,770	$ 1,698
Percent of Total Assets	63.00%	70.00%
Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Amount	$ 818	$ 704
Percent of Total Assets	29.00%	29.00%
Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Amount	$ 237	$ 29
Percent of Total Assets	8.00%	1.00%

Employee Benefit Plans - Sche_3

Employee Benefit Plans - Schedule of Changes in Benefit Obligation and Fair Value of Plan Assets (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018
Change in Projected Benefit Obligation:
Post-retirement Plan Amendment		$ 102,000,000
Change in Plan Assets:
Fair Value of Plan Assets at Beginning of Plan Year	$ 2,431,000,000
Non-qualified Employer Contributions	0	0	$ 0
Fair Value of Plan Assets at End of Plan Year	2,825,000,000	2,431,000,000
Capitalized service costs	3,000,000	3,000,000
Pension Benefits
Actuarial Present Value of Benefit Obligation
Accumulated Benefit Obligation				$ 2,963,000,000	$ 2,623,000,000
Projected Benefit Obligation	2,758,000,000	2,758,000,000	3,002,000,000	3,122,000,000	2,758,000,000
Change in Projected Benefit Obligation:
Projected Benefit Obligation at Beginning of Plan Year	2,758,000,000	3,002,000,000
Service Cost	34,000,000	36,000,000
Interest Cost	103,000,000	92,000,000	92,000,000
Plan Participants' Contributions	0	0
Post-retirement Plan Amendment	0	0
Actuarial Loss (Gain)	418,000,000	(173,000,000)
Benefits Paid	(191,000,000)	(199,000,000)
Benefit Obligation at End of Plan Year	3,122,000,000	2,758,000,000	3,002,000,000
Change in Plan Assets:
Fair Value of Plan Assets at Beginning of Plan Year	2,431,000,000	2,833,000,000
Actual Return on Plan Assets Gain (Loss)	568,000,000	(220,000,000)
Plan Participants' Contributions	0	0
Benefits Paid	(191,000,000)	(199,000,000)
Fair Value of Plan Assets at End of Plan Year	2,825,000,000	2,431,000,000	2,833,000,000
Funded Status at End of Plan Year				(297,000,000)	(327,000,000)
Pension Benefits \| Nonqualified Plan
Change in Plan Assets:
Non-qualified Employer Contributions	17,000,000	17,000,000
Post-retirement Benefits
Actuarial Present Value of Benefit Obligation
Projected Benefit Obligation	118,000,000	118,000,000	250,000,000	117,000,000	118,000,000
Change in Projected Benefit Obligation:
Projected Benefit Obligation at Beginning of Plan Year	118,000,000	250,000,000
Service Cost	1,000,000	2,000,000
Interest Cost	2,000,000	7,000,000	7,000,000
Plan Participants' Contributions	7,000,000	5,000,000
Post-retirement Plan Amendment	0	(102,000,000)
Actuarial Loss (Gain)	22,000,000	(10,000,000)
Benefits Paid	(33,000,000)	(34,000,000)
Benefit Obligation at End of Plan Year	117,000,000	118,000,000	250,000,000
Change in Plan Assets:
Fair Value of Plan Assets at Beginning of Plan Year	0	0
Actual Return on Plan Assets Gain (Loss)	0	0
Plan Participants' Contributions	7,000,000	4,000,000
Benefits Paid	(33,000,000)	(34,000,000)
Fair Value of Plan Assets at End of Plan Year	0	0	$ 0
Funded Status at End of Plan Year				$ (117,000,000)	$ (118,000,000)
Post-retirement Benefits \| Nonqualified Plan
Change in Plan Assets:
Non-qualified Employer Contributions	$ 26,000,000	$ 30,000,000

Employee Benefit Plans - Sche_4

Employee Benefit Plans - Schedule of Amount Recognized in Balance Sheet (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Pension Benefits
Amounts Recorded in Consolidated Balance Sheets [Abstract]
Long-term Assets	$ 25	$ 13
Current Liabilities	(17)	(16)
Long-term Liabilities	(305)	(324)
Net Amount Recognized in Consolidated Balance Sheets	(297)	(327)
Post-retirement Benefits
Amounts Recorded in Consolidated Balance Sheets [Abstract]
Long-term Assets	0	0
Current Liabilities	(20)	(34)
Long-term Liabilities	(97)	(84)
Net Amount Recognized in Consolidated Balance Sheets	$ (117)	$ (118)

Employee Benefit Plans - Benefi

Employee Benefit Plans - Benefit Obligations in Excess of Plan Assets (Details) $ in Millions	Dec. 31, 2019USD ($)
Projected Benefit Obligation
Aggregate fair value of plan assets	$ 2,715
Aggregate benefit obligation	(3,037)
Accumulated Benefit Obligation
Aggregate fair value of plan assets	2,715
Aggregate benefit obligation	$ (2,878)

Employee Benefit Plans - Sche_5

Employee Benefit Plans - Schedule of Net Benefit Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Components of expense/ (income) related to net benefit expense [Abstract]
Total Income Included in Other Income - Net	$ (43)	$ (38)	$ (32)
Restructuring Charge - Non Operating			56
Pension Benefits
Components of expense/ (income) related to net benefit expense [Abstract]
Service Cost Included in Labor and Fringe	31	32	36
Interest Cost	103	92	92
Expected Return on Plan Assets	(171)	(176)	(171)
Amortization of Net Loss	30	41	41
Amortization of Prior Service Cost	0	0	0
Total Income Included in Other Income - Net	(38)	(43)	(38)
Net Periodic Benefit (Credit) Expense	(7)	(11)	(2)
Restructuring Charge - Non Operating	0	0	60
Settlement (Gain) Loss	0	(1)	11
Total (Credit) Expense	(7)	(12)	69
Post-retirement Benefits
Components of expense/ (income) related to net benefit expense [Abstract]
Service Cost Included in Labor and Fringe	1	2	2
Interest Cost	2	7	7
Expected Return on Plan Assets	0	0	0
Amortization of Net Loss	0	0	0
Amortization of Prior Service Cost	(7)	(2)	0
Total Income Included in Other Income - Net	(5)	5	7
Net Periodic Benefit (Credit) Expense	(4)	7	9
Restructuring Charge - Non Operating	0	0	13
Settlement (Gain) Loss	0	0	0
Total (Credit) Expense	$ (4)	$ 7	$ 22

Employee Benefit Plans - Sche_6

Employee Benefit Plans - Schedule of Pre-tax Change in Other Comprehensive Loss (Income) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Pension Benefits
Recognized in the Balance Sheet
Losses (Gains)	$ 21	$ 223
Expense (Income) Recognized in the Income Statement
Amortization of Net Loss	30	41	$ 41
Settlement (Gain) Loss	0	(1)	11
Amortization of Prior Service Costs	0	0	0
Amortization of net losses estimated to be expensed in next fiscal year	57
Post-retirement Benefits
Recognized in the Balance Sheet
Losses (Gains)	22	(112)
Expense (Income) Recognized in the Income Statement
Amortization of Net Loss	0	0	0
Settlement (Gain) Loss	0	0	0
Amortization of Prior Service Costs	$ (7)	$ (2)	$ 0

Employee Benefit Plans - Sche_7

Employee Benefit Plans - Schedule of Weighted-Average Assumptions Used (Details)	3 Months Ended		12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018
Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Benefit Cost for Current Plan Year			6.75%	6.75%
Benefit Cost for Subsequent Plan Year	6.75%		6.75%	6.75%
Discount Rates:
Service Cost for Plan Year			4.40%	3.74%
Interest Cost for Plan Year			3.87%	3.15%
Benefit Obligation at End of Plan Year	4.24%		3.13%	4.24%
Salary Scale Inflation			4.60%	4.60%
Post-retirement Benefits
Discount Rates:
Service Cost for Plan Year	4.14%	3.68%	4.14%	4.14%
Interest Cost for Plan Year	3.45%	2.79%	3.51%	3.45%
Benefit Obligation at End of Plan Year	3.98%		2.87%	3.98%

Debt and Credit Agreements - Sc

Debt and Credit Agreements - Schedule of Long-term Debt Instruments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Finance Lease Rate	15.00%
Subtotal Long-term Debt (including current portion)	$ 16,238	$ 14,757
Finance Leases	4
Less Debt Due within One Year	(245)	(18)
Long-term Debt (excluding current portion)	$ 15,993	14,739
Notes
Debt Instrument [Line Items]
Average Interest Rates	4.40%
Subtotal Long-term Debt (including current portion)	$ 16,056	14,558
Equipment Obligations
Debt Instrument [Line Items]
Average Interest Rates	6.30%
Subtotal Long-term Debt (including current portion)	$ 178	195
Finance Leases
Debt Instrument [Line Items]
Subtotal Long-term Debt (including current portion)		$ 4

Debt and Credit Agreements - Na

Debt and Credit Agreements - Narrative (Details) - USD ($)	Dec. 31, 2019	Oct. 15, 2019	Sep. 12, 2019	Mar. 31, 2019	Feb. 28, 2019	Nov. 15, 2018	Sep. 14, 2018	Feb. 20, 2018
Commercial Paper
Debt Instrument [Line Items]
Line of credit facility capacity							$ 1,000,000,000
Facility, amount outstanding	$ 0
2.40% Notes due 2030
Debt Instrument [Line Items]
Debt issued			$ 400,000,000
Interest rate			2.40%
3.35% Notes due 2049
Debt Instrument [Line Items]
Debt issued			$ 600,000,000
Interest rate			3.35%
3.70% Notes due 2020
Debt Instrument [Line Items]
Interest rate		3.70%
Long-term debt		$ 500,000,000
4.25% Notes due 2029
Debt Instrument [Line Items]
Debt issued					$ 600,000,000
Interest rate					4.25%
4.50% Notes due 2049
Debt Instrument [Line Items]
Debt issued					$ 400,000,000
Interest rate					4.50%
4.25% Notes due 2029
Debt Instrument [Line Items]
Debt issued						$ 350,000,000
Interest rate						4.25%
4.75% Notes due 2048
Debt Instrument [Line Items]
Debt issued						$ 650,000,000
Interest rate						4.75%
3.80% Notes due 2028
Debt Instrument [Line Items]
Debt issued								$ 800,000,000
Interest rate								3.80%
4.30% Notes due 2048
Debt Instrument [Line Items]
Debt issued								$ 850,000,000
Interest rate								4.30%
4.65% Notes due 2068
Debt Instrument [Line Items]
Debt issued								$ 350,000,000
Interest rate								4.65%
Unsecured Revolving Credit Facility \| Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility capacity				$ 1,000,000,000
Unsecured Revolving Credit Facility Due 2024 \| Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility capacity				$ 1,200,000,000
Line of credit facility, amount outstanding	$ 0

Debt and Credit Agreements - _2

Debt and Credit Agreements - Schedule of Long-term Debt Maturities (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Maturities of Long-term Debt [Abstract]
2020	$ 245
2021	401
2022	162
2023	639
2024	551
Thereafter	14,240
Subtotal Long-term Debt (including current portion)	$ 16,238	$ 14,757

Revenues - Disaggregated by Lin

Revenues - Disaggregated by Lines of Business (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Revenue	$ 2,885	$ 2,978	$ 3,061	$ 3,013	$ 3,143	$ 3,129	$ 3,102	$ 2,876	$ 11,937	$ 12,250	$ 11,408
Chemicals
Disaggregation of Revenue [Line Items]
Revenue									2,343	2,339	2,210
Agricultural and Food Products
Disaggregation of Revenue [Line Items]
Revenue									1,410	1,306	1,262
Automotive
Disaggregation of Revenue [Line Items]
Revenue									1,236	1,267	1,195
Forest Products
Disaggregation of Revenue [Line Items]
Revenue									878	850	755
Metals and Equipment
Disaggregation of Revenue [Line Items]
Revenue									741	769	703
Minerals
Disaggregation of Revenue [Line Items]
Revenue									550	518	477
Fertilizers
Disaggregation of Revenue [Line Items]
Revenue									431	442	466
Total Merchandise
Disaggregation of Revenue [Line Items]
Revenue									7,589	7,491	7,068
Coal
Disaggregation of Revenue [Line Items]
Revenue									2,070	2,246	2,107
Intermodal
Disaggregation of Revenue [Line Items]
Revenue									1,760	1,931	1,799
Other
Disaggregation of Revenue [Line Items]
Revenue									$ 518	$ 582	$ 434

Revenues - Narrative (Details)

Revenues - Narrative (Details)	12 Months Ended
Revenues - Narrative (Details)	Dec. 31, 2019
Concentration Risk [Line Items]
Payment period after invoice date	15 days
Minimum
Concentration Risk [Line Items]
Average transit time to complete a shipment	3 days
Maximum
Concentration Risk [Line Items]
Average transit time to complete a shipment	8 days

Revenues - Receivables (Details

Revenues - Receivables (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Accounts Receivable, net	$ 986	$ 1,010
Freight Receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross Receivables	790	846
Allowance for Doubtful Accounts	(21)	(18)
Total Accounts Receivable, net	769	828
Non-Freight Receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gross Receivables	226	190
Allowance for Doubtful Accounts	(9)	(8)
Total Accounts Receivable, net	$ 217	$ 182

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	Jan. 01, 2018	Dec. 22, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Loss Carryforwards [Line Items]
Earnings before income taxes			$ 4,316	$ 4,304	$ 3,142
Income tax adjustment benefit			77	62	21
Non-cash credit to income tax expense		$ 3,500	0	0	3,506
Non-cash credit to income tax expense amount per share (in dollars per share)		$ 3.81
U.S. corporate tax rate	21.00%
Unrecognized tax benefits			13	12	24
Amount of unrecognized tax benefits that may favorably effect the effective income tax rate			10	9	19
Expense (benefit) for changes to reserves for interest and penalties for prior year tax positions			1	(3)	3
Previously recorded liabilities for interest and penalties of prior period tax positions			$ 2	$ 2	$ 6

Income Taxes - Schedule of Brea

Income Taxes - Schedule of Breakdown of Income Tax Expense Between Current and Deferred (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current:
Federal	$ 608	$ 572	$ 787
State	104	144	117
Subtotal Current	712	716	904
Deferred:
Federal	235	275	(3,277)
State	38	4	44
Subtotal Deferred	273	279	(3,233)
Income Tax Expense	$ 985	$ 995	$ (2,329)

Income Taxes - Schedule of Inco

Income Taxes - Schedule of Income Tax Expense Reconciled to Tax Computed at Statutory Rates (Details) - USD ($) $ in Millions	Dec. 22, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Amount
Federal Income Taxes		$ 906	$ 904	$ 1,100
State Income Taxes		108	112	102
Deferred Tax Rate Change	$ (3,500)	0	0	(3,506)
Other		(29)	(21)	(25)
Income Tax Expense		$ 985	$ 995	$ (2,329)
Percent
Federal Income Taxes		21.00%	21.00%	35.00%
State Income Taxes		2.50%	2.60%	3.20%
Deferred Tax Rate Change		0.00%	0.00%	(111.60%)
Other		(0.70%)	(0.50%)	(0.80%)
Income Tax Rate		22.80%	23.10%	(74.20%)

Income Taxes - Schedule of Sign

Income Taxes - Schedule of Significant Components of Deferred Income Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Assets
Pension Plans	$ 71	$ 79
Other Employee Benefit Plans	127	146
Other	426	529
Total	624	754
Liabilities
Accelerated Depreciation	7,020	6,799
Other	565	645
Total	7,585	7,444
Net Deferred Income Tax Liabilities	$ 6,961	$ 6,690

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Equity
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment committee equity target allocation percentage of pension assets	60.00%
Fixed Income
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment committee equity target allocation percentage of pension assets	40.00%
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Amortized cost basis of investments	$ 1,100	$ 340

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Fair Value of Investment Assets (Details) - Fair Value - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investments at fair value	$ 1,084	$ 341
Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investments at fair value	1,084	341
Level 2 \| Certificates of Deposit and Commercial Paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investments at fair value	989	250
Level 2 \| Corporate Bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investments at fair value	59	56
Level 2 \| Government Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total investments at fair value	$ 36	$ 35

Fair Value Measurements - Sch_2

Fair Value Measurements - Schedule of Investment Maturities (Details) - Fair Value - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Less than 1 year	$ 996	$ 253
1 - 5 years	10	14
5 - 10 years	25	26
Greater than 10 years	53	48
Investments at fair value	$ 1,084	$ 341

Fair Value Measurements - Sch_3

Fair Value Measurements - Schedule of Fair Value and Carrying Value of Long-term Debt (Details) - Level 2 - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term Debt (Including Current Maturities)	$ 18,503	$ 14,914
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term Debt (Including Current Maturities)	$ 16,238	$ 14,757

Fair Value Measurements - Sch_4

Fair Value Measurements - Schedule of Pension Plan Assets at Fair Value by Level (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	$ 2,825	$ 2,431
Total investments in the fair value hierarchy	1,952	1,461
Common Stock
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	823	750
Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	78	7
Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	229	3
Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	588	537
Government securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	217	149
Asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	8	10
Derivatives and other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	9	5
Level 1
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	1,130	760
Total investments in the fair value hierarchy	1,130	760
Level 1 \| Common Stock
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	823	750
Level 1 \| Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	78	7
Level 1 \| Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	229	3
Level 1 \| Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	0	0
Level 1 \| Government securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	0	0
Level 1 \| Asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	0	0
Level 1 \| Derivatives and other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	0	0
Level 2
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	822	701
Total investments in the fair value hierarchy	822	701
Level 2 \| Common Stock
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	0	0
Level 2 \| Mutual funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	0	0
Level 2 \| Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	0	0
Level 2 \| Corporate bonds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	588	537
Level 2 \| Government securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	217	149
Level 2 \| Asset-backed securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	8	10
Level 2 \| Derivatives and other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets at fair value	9	5
Investments measured at net asset value
Defined Benefit Plan Disclosure [Line Items]
Investments measured at net asset value	$ 873	$ 970

Other Income - Net (Details)

Other Income - Net (Details) - USD ($) $ in Millions	12 Months Ended
Other Income - Net (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Other Income and Expenses [Abstract]
Cost associated with early redemption of long-term debt included in miscellaneous expense	$ 10
Net Periodic Pension and Post-retirement Benefit Credit	43	$ 38	$ 32
Interest Income	48	32	13
Miscellaneous (Expense) Income	(3)	4	8
Total Other Income - Net	$ 88	$ 74	$ 53

Related Parties and Affiliate_2

Related Parties and Affiliates - Narrative (Details) $ / shares in Units, shares in Millions, $ in Millions	Oct. 17, 2019USD ($)shares	Dec. 22, 2017USD ($)$ / shares	Dec. 31, 2017USD ($)$ / shares	Dec. 31, 2019USD ($)shares	Dec. 31, 2018USD ($)shares	Dec. 31, 2017USD ($)shares	Dec. 26, 2014note
Related Party Transaction [Line Items]
Non-cash credit to income tax expense		$ 3,500		$ 0	$ 0	$ 3,506
Effect of change in tax rate (in dollars per share) \| $ / shares		$ 3.81
Number of shares repurchased (in shares) \| shares				48	72	39
Amount of shares repurchased				$ 3,373	$ 4,671	$ 1,970
Investments in Conrail
Related Party Transaction [Line Items]
Investments in affiliates					943
Corporate Joint Venture \| Conrail
Related Party Transaction [Line Items]
Difference between carrying amount and underlying equity				339
Promissory notes executed \| note							2
Interest expense				6	$ 6	$ 6
Corporate Joint Venture \| Investments in Conrail \| Conrail
Related Party Transaction [Line Items]
Investments in affiliates				$ 982
Corporate Joint Venture \| Voting interest in related party which is also an equity method investment \| Conrail
Related Party Transaction [Line Items]
Ownership percentage				50.00%
Corporate Joint Venture \| Economic interest in related party which is also an equity method investment \| Conrail
Related Party Transaction [Line Items]
Ownership percentage				42.00%
Affiliated Entity
Related Party Transaction [Line Items]
Non-cash credit to income tax expense			$ 142
Effect of change in tax rate (in dollars per share) \| $ / shares			$ 0.10
Affiliated Entity \| TTX
Related Party Transaction [Line Items]
Ownership percentage				20.00%
Equity method investments				$ 743
Affiliated Entity \| MR Argent Advisor LLC
Related Party Transaction [Line Items]
Number of shares repurchased (in shares) \| shares	4.7
Amount of shares repurchased	$ 319

Related Parties and Affiliate_3

Related Parties and Affiliates - Schedule of Future Payments Due under Operating Leases (Details) $ in Millions	Dec. 31, 2019USD ($)
Related Party Transaction [Line Items]
2020	$ 58
2021	54
2022	48
2023	39
2024	37
Thereafter	1,208
Total undiscounted operating lease payments	1,444
Corporate Joint Venture \| Conrail
Related Party Transaction [Line Items]
2020	29
2021	29
2022	29
2023	29
2024	22
Thereafter	0
Total undiscounted operating lease payments	$ 138

Related Parties and Affiliate_4

Related Parties and Affiliates - Schedule of Related Party in the Consolidated Income Statement Components (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Related Party Amounts Consolidated Income Statements [Abstract]
Equity Earnings of Affiliates	$ (91)	$ (96)	$ (219)
Corporate Joint Venture \| Conrail \| Materials, Supplies and Other
Related Party Amounts Consolidated Income Statements [Abstract]
Rents, fees and services	119	117	120
Purchase price amortization and other	4	4	4
Equity Earnings of Affiliates	(42)	(43)	(58)
Total	81	78	66
Affiliated Entity \| TTX \| Materials, Supplies and Other
Related Party Amounts Consolidated Income Statements [Abstract]
Car hire rents	223	223	237
Equity Earnings of Affiliates	(56)	(60)	(157)
Total	$ 167	$ 163	$ 80

Related Parties and Affiliate_5

Related Parties and Affiliates - Schedule of Related Party Consolidated Balance Sheet Components (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Related Party Transaction [Line Items]
Payable to Affiliates	$ 0	$ 0
Corporate Joint Venture \| Conrail \| Accounts Payable
Related Party Transaction [Line Items]
Payable to Affiliates	213	153
Corporate Joint Venture \| Conrail \| Long-term Debt \| 2.89% CSX promissory note due October 2044
Related Party Transaction [Line Items]
Promissory notes payable to Conrail subsidiary	$ 73	$ 73
Related party note, interest rate (as a percent)	2.89%	2.89%
Corporate Joint Venture \| Conrail \| Long-term Debt \| 2.89% CSXT promissory note due October 2044
Related Party Transaction [Line Items]
Promissory notes payable to Conrail subsidiary	$ 151	$ 151
Related party note, interest rate (as a percent)	2.89%	2.89%
Affiliated Entity \| TTX \| Accounts Payable
Related Party Transaction [Line Items]
Payable to Affiliates	$ 34	$ 36

Other Comprehensive Income _ _3

Other Comprehensive Income / (Loss) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Comprehensive earnings		$ 3,317	$ 3,134	$ 5,625
Other Comprehensive Income (Loss):
Reclassification of Stranded Tax Effects			(107)
Income Before Reclassifications		(48)	(119)	161
Amounts Reclassified to Net Earnings		31	32	58
Tax (Expense) Benefit		3	19	(65)
Total Other Comprehensive (Loss) Income		(14)	(175)	154
Pension and Other Post-Employment Benefits
Other Comprehensive Income (Loss):
Beginning Balance		(604)	(440)	(580)
Reclassification of Stranded Tax Effects			(108)
Income Before Reclassifications		(43)	(111)	148
Amounts Reclassified to Net Earnings		23	38	56
Tax (Expense) Benefit		5	17	(64)
Total Other Comprehensive (Loss) Income		(15)	(164)	140
Ending Balance		(619)	(604)	(440)
Other
Other Comprehensive Income (Loss):
Beginning Balance		(57)	(46)	(60)
Reclassification of Stranded Tax Effects			1
Income Before Reclassifications		(5)	(8)	13
Amounts Reclassified to Net Earnings		8	(6)	2
Tax (Expense) Benefit		(2)	2	(1)
Total Other Comprehensive (Loss) Income		1	(11)	14
Ending Balance		(56)	(57)	(46)
Accumulated Other Comprehensive Income (Loss)
Other Comprehensive Income (Loss):
Beginning Balance		(661)	(486)	(640)
Total Other Comprehensive (Loss) Income	[1]	(14)	(175)	154
Ending Balance		$ (675)	$ (661)	$ (486)

[1]	Accumulated Other Comprehensive Loss year-end balances shown above are net of tax. The associated taxes were $184 million , $180 million and $162 million for 2019 , 2018 and 2017 , respectively. For additional information see Note 16, Other Comprehensive Income.

Quarterly Financial Data (Una_3

Quarterly Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Revenue	$ 2,885	$ 2,978	$ 3,061	$ 3,013	$ 3,143	$ 3,129	$ 3,102	$ 2,876	$ 11,937	$ 12,250	$ 11,408
Operating Income	1,154	1,287	1,305	1,219	1,249	1,293	1,283	1,044	4,965	4,869	3,720
Net Earnings	$ 771	$ 856	$ 870	$ 834	$ 843	$ 894	$ 877	$ 695	$ 3,331	$ 3,309	$ 5,471
Earnings Per Share, Basic (in dollars per share)	$ 0.99	$ 1.08	$ 1.08	$ 1.02	$ 1.02	$ 1.05	$ 1.02	$ 0.78	$ 4.18	$ 3.86	$ 6.01
Earnings Per Share, Assuming Dilution (in dollars per share)	$ 0.99	$ 1.08	$ 1.08	$ 1.02	$ 1.01	$ 1.05	$ 1.01	$ 0.78	$ 4.17	$ 3.84	$ 5.99

Summarized Consolidating Fina_3

Summarized Consolidating Financial Data (Consolidating Income Statement) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Consolidated Income Statement
Revenue	$ 2,885	$ 2,978	$ 3,061	$ 3,013	$ 3,143	$ 3,129	$ 3,102	$ 2,876	$ 11,937	$ 12,250	$ 11,408
Expense									6,972	7,381	7,688
Operating Income	1,154	1,287	1,305	1,219	1,249	1,293	1,283	1,044	4,965	4,869	3,720
Equity in Earnings of Subsidiaries									0	0	0
Interest Expense									(737)	(639)	(546)
Other Income - Net									88	74	(32)
Earnings Before Income Taxes									4,316	4,304	3,142
Income Tax Benefit (Expense)									(985)	(995)	2,329
Net Earnings	$ 771	$ 856	$ 870	$ 834	$ 843	$ 894	$ 877	$ 695	3,331	3,309	5,471
Total Comprehensive Earnings									3,317	3,134	5,625
Eliminations and Other
Consolidated Income Statement
Revenue									81	76	74
Expense									(167)	(143)	(163)
Operating Income									248	219	237
Equity in Earnings of Subsidiaries									(3,505)	(3,580)	(5,810)
Interest Expense									183	142	65
Other Income - Net									(144)	(102)	(20)
Earnings Before Income Taxes									(3,218)	(3,321)	(5,528)
Income Tax Benefit (Expense)									(106)	(62)	4
Net Earnings									(3,324)	(3,383)	(5,524)
Total Comprehensive Earnings									(3,306)	(3,441)	(5,538)
CSX Corporation
Consolidated Income Statement
Revenue									0	0	0
Expense									(549)	(344)	(158)
Operating Income									549	344	158
Equity in Earnings of Subsidiaries									3,505	3,580	5,810
Interest Expense									(878)	(742)	(582)
Other Income - Net									25	24	7
Earnings Before Income Taxes									3,201	3,206	5,393
Income Tax Benefit (Expense)									130	103	78
Net Earnings									3,331	3,309	5,471
Total Comprehensive Earnings									3,317	3,134	5,625
CSX Transportation
Consolidated Income Statement
Revenue									11,856	12,174	11,334
Expense									7,688	7,868	8,009
Operating Income									4,168	4,306	3,325
Equity in Earnings of Subsidiaries									0	0	0
Interest Expense									(42)	(39)	(29)
Other Income - Net									207	152	(19)
Earnings Before Income Taxes									4,333	4,419	3,277
Income Tax Benefit (Expense)									(1,009)	(1,036)	2,247
Net Earnings									3,324	3,383	5,524
Total Comprehensive Earnings									$ 3,306	$ 3,441	$ 5,538

Summarized Consolidating Fina_4

Summarized Consolidating Financial Data (Consolidating Balance Sheets) (Details) - USD ($) $ / shares in Units, $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 30, 2016
Current Assets:
Cash and Cash Equivalents	$ 958	$ 858	$ 401	$ 603
Short-term Investments	996	253
Accounts Receivable - Net	986	1,010
Receivable from Affiliates	0	0
Materials and Supplies	261	263
Other Current Assets	77	181
Total Current Assets	3,278	2,565
Properties	45,100	44,805
Accumulated Depreciation	(12,932)	(12,807)
Properties - Net (Note 6)	32,168	31,998
Right of Use Lease Asset (Note 7)	532	0
Other Long-term Assets	400	387
Total Assets	38,257	36,729
Current Liabilities:
Accounts Payable	1,043	949
Labor and Fringe Benefits Payable	489	550
Payable to Affiliates	0	0
Casualty, Environmental and Other Reserves	100	113
Current Maturities of Long-term Debt	245	18
Income and Other Taxes Payable	69	106
Other Current Liabilities	205	179
Total Current Liabilities	2,151	1,915
Casualty, Environmental and Other Reserves	205	211
Long-term Debt	15,993	14,739
Deferred Income Taxes - Net	6,961	6,690
Long-term lease liabilities	493	0
Other Long-term Liabilities	591	594
Total Liabilities	26,394	24,149
Shareholders' Equity:
Common Stock, $1 Par Value	773	818
Other Capital	346	249
Retained Earnings	11,404	12,157
Accumulated Other Comprehensive Loss	(675)	(661)
Noncontrolling Minority Interest	15	17
Total Shareholders' Equity	11,863	12,580	14,721	11,694
Total Liabilities and Shareholders' Equity	$ 38,257	$ 36,729
Common stock par value (in dollars per share)	$ 1	$ 1
Investments in Conrail
Current Assets:
Investment in Affiliates and Other Companies		$ 943
Affiliates and Other Companies
Current Assets:
Investment in Affiliates and Other Companies	$ 897	836
Investment in Consolidated Subsidiaries
Current Assets:
Investment in Affiliates and Other Companies	0	0
Eliminations and Other
Current Assets:
Cash and Cash Equivalents	8	12	6	17
Short-term Investments	7	3
Accounts Receivable - Net	13	6
Receivable from Affiliates	(8,459)	(6,234)
Materials and Supplies	0	0
Other Current Assets	21	14
Total Current Assets	(8,410)	(6,199)
Properties	2,989	2,907
Accumulated Depreciation	(1,732)	(1,612)
Properties - Net (Note 6)	1,257	1,295
Right of Use Lease Asset (Note 7)	18
Other Long-term Assets	(232)	(213)
Total Assets	(40,900)	(36,191)
Current Liabilities:
Accounts Payable	60	54
Labor and Fringe Benefits Payable	65	69
Payable to Affiliates	(10,126)	(7,606)
Casualty, Environmental and Other Reserves	13	14
Current Maturities of Long-term Debt	0	0
Income and Other Taxes Payable	15	4
Other Current Liabilities	13	6
Total Current Liabilities	(9,960)	(7,459)
Casualty, Environmental and Other Reserves	36	35
Long-term Debt	0	0
Deferred Income Taxes - Net	286	223
Long-term lease liabilities	12
Other Long-term Liabilities	(316)	(338)
Total Liabilities	(9,942)	(7,539)
Shareholders' Equity:
Common Stock, $1 Par Value	(181)	(181)
Other Capital	(5,096)	(5,096)
Retained Earnings	(25,646)	(23,322)
Accumulated Other Comprehensive Loss	(35)	(53)
Noncontrolling Minority Interest	0	0
Total Shareholders' Equity	(30,958)	(28,652)
Total Liabilities and Shareholders' Equity	(40,900)	(36,191)
Eliminations and Other \| Investments in Conrail
Current Assets:
Investment in Affiliates and Other Companies	982	943
Eliminations and Other \| Affiliates and Other Companies
Current Assets:
Investment in Affiliates and Other Companies	13	16
Eliminations and Other \| Investment in Consolidated Subsidiaries
Current Assets:
Investment in Affiliates and Other Companies	(34,528)	(32,033)
CSX Corporation
Current Assets:
Cash and Cash Equivalents	814	716	274	305
Short-term Investments	989	250
Accounts Receivable - Net	4	1
Receivable from Affiliates	1,054	1,020
Materials and Supplies	0	0
Other Current Assets	26	63
Total Current Assets	2,887	2,050
Properties	1	1
Accumulated Depreciation	(1)	(1)
Properties - Net (Note 6)	0	0
Right of Use Lease Asset (Note 7)	0
Other Long-term Assets	3	2
Total Assets	37,379	34,046
Current Liabilities:
Accounts Payable	153	132
Labor and Fringe Benefits Payable	38	41
Payable to Affiliates	9,552	6,973
Casualty, Environmental and Other Reserves	0	0
Current Maturities of Long-term Debt	0	0
Income and Other Taxes Payable	(286)	(290)
Other Current Liabilities	0	11
Total Current Liabilities	9,457	6,867
Casualty, Environmental and Other Reserves	0	0
Long-term Debt	15,534	14,029
Deferred Income Taxes - Net	(152)	(134)
Long-term lease liabilities	0
Other Long-term Liabilities	692	721
Total Liabilities	25,531	21,483
Shareholders' Equity:
Common Stock, $1 Par Value	773	818
Other Capital	346	249
Retained Earnings	11,404	12,157
Accumulated Other Comprehensive Loss	(675)	(661)
Noncontrolling Minority Interest	0	0
Total Shareholders' Equity	11,848	12,563
Total Liabilities and Shareholders' Equity	37,379	34,046
CSX Corporation \| Investments in Conrail
Current Assets:
Investment in Affiliates and Other Companies	0	0
CSX Corporation \| Affiliates and Other Companies
Current Assets:
Investment in Affiliates and Other Companies	(39)	(39)
CSX Corporation \| Investment in Consolidated Subsidiaries
Current Assets:
Investment in Affiliates and Other Companies	34,528	32,033
CSX Transportation
Current Assets:
Cash and Cash Equivalents	136	130	$ 121	$ 281
Short-term Investments	0	0
Accounts Receivable - Net	969	1,003
Receivable from Affiliates	7,405	5,214
Materials and Supplies	261	263
Other Current Assets	30	104
Total Current Assets	8,801	6,714
Properties	42,110	41,897
Accumulated Depreciation	(11,199)	(11,194)
Properties - Net (Note 6)	30,911	30,703
Right of Use Lease Asset (Note 7)	514
Other Long-term Assets	629	598
Total Assets	41,778	38,874
Current Liabilities:
Accounts Payable	830	763
Labor and Fringe Benefits Payable	386	440
Payable to Affiliates	574	633
Casualty, Environmental and Other Reserves	87	99
Current Maturities of Long-term Debt	245	18
Income and Other Taxes Payable	340	392
Other Current Liabilities	192	162
Total Current Liabilities	2,654	2,507
Casualty, Environmental and Other Reserves	169	176
Long-term Debt	459	710
Deferred Income Taxes - Net	6,827	6,601
Long-term lease liabilities	481
Other Long-term Liabilities	215	211
Total Liabilities	10,805	10,205
Shareholders' Equity:
Common Stock, $1 Par Value	181	181
Other Capital	5,096	5,096
Retained Earnings	25,646	23,322
Accumulated Other Comprehensive Loss	35	53
Noncontrolling Minority Interest	15	17
Total Shareholders' Equity	30,973	28,669
Total Liabilities and Shareholders' Equity	41,778	38,874
CSX Transportation \| Investments in Conrail
Current Assets:
Investment in Affiliates and Other Companies	0	0
CSX Transportation \| Affiliates and Other Companies
Current Assets:
Investment in Affiliates and Other Companies	923	859
CSX Transportation \| Investment in Consolidated Subsidiaries
Current Assets:
Investment in Affiliates and Other Companies	$ 0	$ 0

Summarized Consolidating Fina_5

Summarized Consolidating Financial Data (Consolidating Cash Flow Statements) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Activities
Net Cash Provided by (Used in) Operating Activities	$ 4,850	$ 4,641	$ 3,472
Investing Activities
Property Additions	(1,657)	(1,745)	(2,040)
Purchase of Short-term Investments	(2,838)	(736)	(782)
Proceeds from Sales of Short-term Investments	2,108	505	1,193
Proceeds from Property Dispositions	254	319	97
Other Investing Activities	31	(27)	37
Net Cash Used in Investing Activities	(2,102)	(1,684)	(1,495)
Financing Activities
Long-term Debt Issued	2,000	3,000	850
Long-term Debt Repaid	(518)	(19)	(333)
Dividends Paid	(763)	(751)	(708)
Shares Repurchased	(3,373)	(4,671)	(1,970)
Other Financing Activities	6	(59)	(18)
Net Cash Used in Financing Activities	(2,648)	(2,500)	(2,179)
Net Increase (Decrease) in Cash and Cash Equivalents	100	457	(202)
Cash and Cash Equivalents at Beginning of Period	858	401	603
Cash and Cash Equivalents at End of Period	958	858	401
Eliminations and Other
Operating Activities
Net Cash Provided by (Used in) Operating Activities	(862)	(198)	(359)
Investing Activities
Property Additions	(151)	(165)	(192)
Purchase of Short-term Investments	0	(2)	(8)
Proceeds from Sales of Short-term Investments	3	20	3
Proceeds from Property Dispositions	0	0	0
Other Investing Activities	6	(661)	(55)
Net Cash Used in Investing Activities	(142)	(808)	(252)
Financing Activities
Long-term Debt Issued	0	0	0
Long-term Debt Repaid	0	0	0
Dividends Paid	1,000	1,000	600
Shares Repurchased	0	0	0
Other Financing Activities	0	12	0
Net Cash Used in Financing Activities	1,000	1,012	600
Net Increase (Decrease) in Cash and Cash Equivalents	(4)	6	(11)
Cash and Cash Equivalents at Beginning of Period	12	6	17
Cash and Cash Equivalents at End of Period	8	12	6
CSX Corporation
Operating Activities
Net Cash Provided by (Used in) Operating Activities	3,440	3,182	1,719
Investing Activities
Property Additions	0	0	0
Purchase of Short-term Investments	(2,838)	(734)	(774)
Proceeds from Sales of Short-term Investments	2,105	485	1,190
Proceeds from Property Dispositions	0	0	0
Other Investing Activities	15	(4)	(2)
Net Cash Used in Investing Activities	(718)	(253)	414
Financing Activities
Long-term Debt Issued	2,000	3,000	850
Long-term Debt Repaid	(500)	0	(313)
Dividends Paid	(763)	(751)	(708)
Shares Repurchased	(3,373)	(4,671)	(1,970)
Other Financing Activities	12	(65)	(23)
Net Cash Used in Financing Activities	(2,624)	(2,487)	(2,164)
Net Increase (Decrease) in Cash and Cash Equivalents	98	442	(31)
Cash and Cash Equivalents at Beginning of Period	716	274	305
Cash and Cash Equivalents at End of Period	814	716	274
CSX Transportation
Operating Activities
Net Cash Provided by (Used in) Operating Activities	2,272	1,657	2,112
Investing Activities
Property Additions	(1,506)	(1,580)	(1,848)
Purchase of Short-term Investments	0	0	0
Proceeds from Sales of Short-term Investments	0	0	0
Proceeds from Property Dispositions	254	319	97
Other Investing Activities	10	638	94
Net Cash Used in Investing Activities	(1,242)	(623)	(1,657)
Financing Activities
Long-term Debt Issued	0	0	0
Long-term Debt Repaid	(18)	(19)	(20)
Dividends Paid	(1,000)	(1,000)	(600)
Shares Repurchased	0	0	0
Other Financing Activities	(6)	(6)	5
Net Cash Used in Financing Activities	(1,024)	(1,025)	(615)
Net Increase (Decrease) in Cash and Cash Equivalents	6	9	(160)
Cash and Cash Equivalents at Beginning of Period	130	121	281
Cash and Cash Equivalents at End of Period	$ 136	$ 130	$ 121