CSX (CSX) 10-K14 Feb 242023 FY Annual reportFinancial data

Company Profile

Cover

Cover - USD ($) $ in Billions	12 Months Ended
Cover - USD ($) $ in Billions	Dec. 31, 2023	Jan. 31, 2024	Jun. 30, 2023
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2023
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
ICFR Auditor Attestation Flag	true
Document Financial Statement Error Correction [Flag]	false
Entity Shell Company	false
Entity Public Float			$ 68
Entity Common Stock, Shares Outstanding		1,959,134,342
Documents Incorporated by Reference	Portions of the Registrant’s Definitive Proxy Statement (the “Proxy Statement”) to be filed no later than 120 days after the end of the fiscal year with respect to its 2024 annual meeting of shareholders.
Entity Central Index Key	0000277948
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	FY
Amendment Flag	false

Audit Information

Audit Information	12 Months Ended
Audit Information	Dec. 31, 2023
Audit Information [Abstract]
Auditor Firm ID	42
Auditor Name	Ernst & Young LLP
Auditor Location	Jacksonville, Florida

CONSOLIDATED INCOME STATEMENTS

CONSOLIDATED INCOME STATEMENTS - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Statement [Abstract]
Revenue	$ 14,657	$ 14,853	$ 12,522
Expense
Labor and Fringe	3,024	2,861	2,550
Purchased Services and Other	2,764	2,685	2,135
Depreciation and Amortization	1,611	1,500	1,420
Fuel	1,377	1,626	913
Equipment and Other Rents	354	396	364
Gains on Property Dispositions	(34)	(238)	(454)
Total Expense	9,096	8,830	6,928
Operating Income	5,561	6,023	5,594
Interest Expense	(809)	(742)	(722)
Other Income - Net (Note 14)	139	133	79
Earnings Before Income Taxes	4,891	5,414	4,951
Income Tax Expense (Note 12)	(1,176)	(1,248)	(1,170)
Net Earnings	$ 3,715	$ 4,166	$ 3,781
Net Earnings Per Share
Basic (in dollars per share)	$ 1.85	$ 1.95	$ 1.68
Assuming Dilution (in dollars per share)	$ 1.85	$ 1.95	$ 1.68
Average Common Shares Outstanding (Millions)
Basic (shares)	2,008	2,136	2,250
Assuming Dilution (shares)	2,013	2,141	2,255

CONSOLIDATED COMPREHENSIVE INCO

CONSOLIDATED COMPREHENSIVE INCOME STATEMENTS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Comprehensive Income [Abstract]
Net Earnings	$ 3,715	$ 4,166	$ 3,781
Other Comprehensive Income (Loss) - Net of Tax:
Pension and Other Post-Employment Benefits	74	(66)	167
Interest Rate Derivatives	0	80	8
Other	2	6	15
Total Other Comprehensive Income (Note 16)	76	20	190
Total Comprehensive Earnings	$ 3,791	$ 4,186	$ 3,971

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($)	Dec. 31, 2023	Dec. 31, 2022
Current Assets:
Cash and Cash Equivalents	$ 1,353,000,000	$ 1,958,000,000
Short-term Investments	83,000,000	129,000,000
Accounts Receivable - Net (Note 11)	1,393,000,000	1,313,000,000
Materials and Supplies	446,000,000	341,000,000
Other Current Assets	109,000,000	108,000,000
Total Current Assets	3,384,000,000	3,849,000,000
Properties	50,320,000,000	48,105,000,000
Accumulated Depreciation	(15,385,000,000)	(13,863,000,000)
Properties - Net (Note 6)	34,935,000,000	34,242,000,000
Investment in Affiliates and Other Companies (Note 15)	2,397,000,000	2,292,000,000
Right of Use Lease Asset (Note 7)	498,000,000	505,000,000
Goodwill and Other Intangible Assets - Net (Note 18)	506,000,000	502,000,000
Other Long-term Assets	688,000,000	522,000,000
Total Assets	42,408,000,000	41,912,000,000
Current Liabilities:
Accounts Payable	1,237,000,000	1,130,000,000
Labor and Fringe Benefits Payable	517,000,000	707,000,000
Casualty, Environmental and Other Reserves (Note 5)	144,000,000	144,000,000
Current Maturities of Long-term Debt (Note 10)	558,000,000	151,000,000
Income and Other Taxes Payable	525,000,000	111,000,000
Other Current Liabilities	243,000,000	228,000,000
Total Current Liabilities	3,224,000,000	2,471,000,000
Casualty, Environmental and Other Reserves (Note 5)	296,000,000	292,000,000
Long-term Debt (Note 10)	17,975,000,000	17,896,000,000
Deferred Income Taxes - Net (Note 12)	7,746,000,000	7,569,000,000
Long-term Lease Liability (Note 7)	491,000,000	488,000,000
Other Long-term Liabilities	543,000,000	571,000,000
Total Liabilities	30,275,000,000	29,287,000,000
Shareholders' Equity:
Common Stock, $1 Par Value (Note 3)	1,959,000,000	2,066,000,000
Other Capital	691,000,000	574,000,000
Retained Earnings	9,790,000,000	10,363,000,000
Accumulated Other Comprehensive Loss (Note 16)	(312,000,000)	(388,000,000)
Non-controlling Minority Interest	5,000,000	10,000,000
Total Shareholders' Equity	12,133,000,000	12,625,000,000
Total Liabilities and Shareholders' Equity	$ 42,408,000,000	$ 41,912,000,000

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2023	Dec. 31, 2022
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, 2023	Dec. 31, 2022	Dec. 31, 2021
OPERATING ACTIVITIES
Net Earnings	$ 3,715	$ 4,166	$ 3,781
Adjustments to Reconcile Net Earnings to Net Cash
Depreciation and Amortization	1,611	1,500	1,420
Deferred Income Taxes	140	117	167
Gains on Property Dispositions	(34)	(238)	(454)
Other Operating Activities	(5)	(17)	12
Changes in Operating Assets and Liabilities:
Accounts Receivable	(51)	(101)	(141)
Other Current Assets	(120)	(22)	(25)
Accounts Payable	83	140	128
Income and Other Taxes Payable	431	(39)	72
Other Current Liabilities	(221)	113	139
Net Cash Provided by Operating Activities	5,549	5,619	5,099
INVESTING ACTIVITIES
Property Additions	(2,281)	(2,133)	(1,791)
Purchases of Short-term Investments	(104)	(59)	(75)
Proceeds from Sales of Short-term Investments	153	9	5
Proceeds and Advances from Property Dispositions	52	246	529
Business Acquisition, Net of Cash Acquired (Note 17)	(31)	(227)	(541)
Other Investing Activities	(76)	33	(4)
Net Cash Used in Investing Activities	(2,287)	(2,131)	(1,877)
FINANCING ACTIVITIES
Shares Repurchased	(3,482)	(4,731)	(2,886)
Dividends Paid	(882)	(852)	(839)
Long-term Debt Repaid	(153)	(186)	(426)
Long-term Debt Issued (Note 10)	600	2,000	0
Other Financing Activities	50	0	39
Net Cash Used in Financing Activities	(3,867)	(3,769)	(4,112)
Net Decrease in Cash and Cash Equivalents	(605)	(281)	(890)
CASH AND CASH EQUIVALENTS
Cash and Cash Equivalents at Beginning of Period	1,958	2,239	3,129
Cash and Cash Equivalents at End of Period	1,353	1,958	2,239
SUPPLEMENTAL CASH FLOW INFORMATION
Issuance of Common Stock as Consideration for Acquisition	0	422	0
Interest Paid - Net of Amounts Capitalized	806	729	718
Income Taxes Paid	$ 630	$ 1,167	$ 931

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 (Loss) Income		Non- controlling Minority Interest
Stockholders' Equity, beginning balance (in shares) at Dec. 31, 2020		2,287,587
Shareholders' Equity, beginning balance at Dec. 31, 2020	$ 13,110		$ 2,440	$ 11,259	$ (598)	[1]	$ 9
Comprehensive Earnings:
Net Earnings	3,781			3,781
Other Comprehensive Income (Note 16)	190				190	[1]
Total Comprehensive Earnings	3,971
Common stock dividends	$ (839)			(839)
Share Repurchases (in shares)	(90,000)	(90,431)
Share Repurchases	$ (2,886)		(90)	(2,796)
Other (in shares)		4,631
Other	144		(82)	225			1
Stockholders' Equity, ending balance (in shares) at Dec. 31, 2021		2,201,787
Shareholders' Equity, ending balance at Dec. 31, 2021	13,500		2,268	11,630	(408)	[1]	10
Comprehensive Earnings:
Accumulated other comprehensive loss, tax					107
Net Earnings	4,166			4,166
Other Comprehensive Income (Note 16)	20				20	[1]
Total Comprehensive Earnings	4,186
Common stock dividends	$ (852)			(852)
Share Repurchases (in shares)	(151,000)	(151,419)
Share Repurchases	$ (4,731)		(151)	(4,580)
Issuance of common stock for acquisition of Pan Am Systems, Inc. (in shares)		13,173
Issuance of common stock for acquisition of Pan Am Systems, Inc.	422		422
Other (in shares)		2,826
Other	100		101	(1)
Stockholders' Equity, ending balance (in shares) at Dec. 31, 2022		2,066,367
Shareholders' Equity, ending balance at Dec. 31, 2022	12,625		2,640	10,363	(388)	[1]	10
Comprehensive Earnings:
Accumulated other comprehensive loss, tax					122
Net Earnings	3,715			3,715
Other Comprehensive Income (Note 16)	76				76	[1]
Total Comprehensive Earnings	3,791
Common stock dividends	$ (882)			(882)
Share Repurchases (in shares)	(112,000)	(112,484)
Share Repurchases	$ (3,482)		(112)	(3,370)
Excise Tax on Net Share Repurchases	(33)			(33)
Other (in shares)		4,874
Other	$ 114		122	(3)			(5)
Stockholders' Equity, ending balance (in shares) at Dec. 31, 2023	1,958,000	1,958,757
Shareholders' Equity, ending balance at Dec. 31, 2023	$ 12,133		$ 2,650	$ 9,790	(312)	[1]	$ 5
Comprehensive Earnings:
Accumulated other comprehensive loss, tax					$ 84

[1]Accumulated Other Comprehensive Loss year-end balances shown above are net of tax. The associated taxes were $84 million, $122 million, and $107 million for 2023, 2022 and 2021, respectively. For additional information see Note 16, Other Comprehensive Income (Loss).

CONSOLIDATED STATEMENTS OF CH_2

CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (Parenthetical) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Statement of Stockholders' Equity [Abstract]
Common stock dividends, per share (in dollars per share)	$ 0.44	$ 0.40	$ 0.37

Nature of Operations and Signif

Nature of Operations and Significant Accounting Policies	12 Months Ended
Nature of Operations and Significant Accounting Policies	Dec. 31, 2023
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 and serves major population centers in 26 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 240 short-line and regional railroads. On June 1, 2022, CSX completed its acquisition of Pan Am Systems, Inc. (“Pan Am”), which is the parent company of Pan Am Railways, Inc. This acquisition expands CSXT’s reach in the Northeastern United States. For further details, refer to Note 17, Business Combinations. 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 Quality Carriers, Inc. ("Quality Carriers"), 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. Effective July 1, 2021, CSX acquired Quality Carriers, the largest provider of bulk liquid chemicals truck transportation in North America. For further details, refer to Note 17, Business Combinations. CSX Intermodal Terminals owns and operates a system of intermodal terminals, predominantly in the eastern United States, and also provides drayage services (the pickup and delivery of intermodal shipments) for certain customers. 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 include 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 2023, the Company's services generated $14.7 billion of revenue and served four primary lines of business: merchandise, intermodal, coal and trucking. • The merchandise business shipped 2.6 million carloads (43% of volume) and generated $8.7 billion in revenue (59% of revenue) in 2023. The Company’s merchandise business is comprised of shipments in the following diverse markets: chemicals, agricultural and food products, minerals, automotive, forest products, metals and equipment, and fertilizers. • The intermodal business shipped 2.8 million units (45% of volume) and generated $2.1 billion in revenue (14% of revenue) in 2023. 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. • The coal business shipped 755 thousand carloads (12% of volume) and generated $2.5 billion in revenue (17% of revenue) in 2023. 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. Most of the export coal the Company transports is used for steelmaking, while the majority of domestic coal the Company ships is used for electricity generation. • The trucking business generated $882 million, or 6%, of revenue in 2023. Trucking revenue includes revenue from the operations of Quality Carriers, which was acquired by CSX effective July 1, 2021. Other revenue accounted for 4% of the Company’s total revenue in 2023. This category includes revenue from regional subsidiary railroads and incidental charges, including intermodal storage and equipment usage, demurrage and switching. Revenue from regional subsidiary railroads includes shipments by railroads that the Company does not directly operate. Intermodal storage represents charges for customer storage of containers at an intermodal terminal, ramp facility or offsite location beyond a specified period of time. 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. The Company has two operating segments: rail and trucking. Although the Company provides a breakdown of revenue by line of business, the overall financial and operational performance of the railroad is analyzed as one operating segment due to the integrated nature of the rail network. As the trucking segment is not material for separate disclosure, the results of all operations are included in one reportable segment. Employees The Company's number of employees was more than 23,000 as of December 2023, which includes approximately 17,700 union employees. Most of the Company’s employees provide or support transportation services. NOTE 1. Nature of Operations and Significant Accounting Policies, continued 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, 2023 and December 31, 2022, and the consolidated statements of income, comprehensive income, cash flows and changes in shareholders’ equity for the years ended 2023, 2022 and 2021. 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. 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 and environmental reserves (see Note 5, Casualty, Environmental and Other Reserves ); • pension plan accounting (see Note 9, Employee Benefit Plans ); and • depreciation policies for assets under the group-life method (see Note 6, Properties ) Fiscal Year The Company's fiscal periods are based upon the calendar year. Except as otherwise specified, references to full years indicate CSX’s fiscal years ended on December 31, 2023, December 31, 2022, and December 31, 2021. 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 Affiliates and Other Companies on the consolidated balance sheets. NOTE 1. Nature of Operations and Significant Accounting Policies, continued 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 approximates 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 cost 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 In March 2020, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2020-04, Facilitation of the Effects of Reference Rate Reform on Financial Reporting . As the London Interbank Offered Rate ("LIBOR") is no longer available as of July 2023, this standard update provides practical expedients for contract modifications made as part of the transition from LIBOR to alternative reference rates. The guidance was effective upon issuance and at present can generally be applied through December 31, 2024. The Company applied the practical expedient to its forward starting interest rate swaps effective June 30, 2023. See Note 10, Debt and Credit Agreements , for additional information. The Company does not have any other contracts that are affected by the transition from LIBOR. In November 2023, the FASB issued ASU 2023-07, Improvements to Reportable Segment Disclosures . This standard update requires additional interim and annual disclosures about a reportable segment’s expenses, even for companies with only one reportable segment. The Company is required to adopt the guidance for its 2024 annual report filed on Form 10-K, though early adoption is permitted. The Company is currently evaluating the impact of these amendments on its disclosures, but this standard update will not impact the Company's results of operations or financial position. In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures . This standard update requires additional interim and annual disclosures about a company’s income taxes, including more detailed information around the annual rate reconciliation and income taxes paid. The Company is required to adopt the guidance for its 2025 annual report filed on Form 10-K, though early adoption is permitted. The Company is currently evaluating the impact of these amendments on its disclosures, but this standard update will not impact the Company's results of operations or financial position.

Earnings Per Share

Earnings Per Share	12 Months Ended
Earnings Per Share	Dec. 31, 2023
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: Years Ended 2023 2022 2021 Numerator (Dollars in Millions) : Net Earnings $ 3,715 $ 4,166 $ 3,781 Denominator (Units in Millions) : Average Common Shares Outstanding 2,008 2,136 2,250 Other Potentially Dilutive Common Shares 5 5 5 Average Common Shares Outstanding, Assuming Dilution 2,013 2,141 2,255 Net Earnings Per Share, Basic $ 1.85 $ 1.95 $ 1.68 Net Earnings Per Share, Assuming Dilution $ 1.85 $ 1.95 $ 1.68 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 stock options, performance and restricted stock units. 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. The total average outstanding equity awards that were excluded from the diluted earnings per share calculation because their effect was antidilutive is in the table below. Years Ended 2023 2022 2021 Antidilutive Stock Options Excluded from Diluted EPS (Units in Millions) 3 3 2 Share Repurchase Programs During November 2023, the share repurchase program announced in July 2022 was completed and the Company began repurchasing shares under the $5 billion share repurchase program approved on October 17, 2023. Total repurchase authority remaining was $4.8 billion as of December 31, 2023. Previous share repurchase programs were announced in October 2020 and January 2019 and were completed in July 2022 and June 2021, respectively. 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 2023, 2022 and 2021, CSX repurchased the following shares: Years Ended 2023 2022 2021 Shares Repurchased (Units in Millions) 112 151 90 Cost of Shares (Dollars in Millions) $ 3,482 $ 4,731 $ 2,886 Average Price Paid per Share $ 30.95 $ 31.25 $ 31.91 The Inflation Reduction Act of 2022 imposes a nondeductible 1% excise tax on the net value of most share repurchases made after December 31, 2022. Excise tax commensurate with net share repurchases is reflected in equity and a corresponding liability for excise taxes payable is included in other current liabilities on the consolidated balance sheet. Amounts shown in the table above exclude the impact of this excise tax. Structured Share Repurchases Periodically, CSX enters into structured agreements for the repurchase of CSX shares. Upon execution of each agreement, the Company pays a fixed amount of cash in exchange for the right to receive either CSX stock or a predetermined amount of cash, including a premium. Shares acquired through these structured share repurchase agreements were recorded in common stock and retained earnings and are included in the share repurchases table above. There were no repurchases under a structured agreement in 2023 or 2022. In 2021, the Company paid a net total of approximately $378 million and received approximately 12 million shares as a result of entering into and settling structured share repurchase agreements. Premiums received were not material. Dividend Increase

Shareholders' Equity

Shareholders' Equity	12 Months Ended
Shareholders' Equity	Dec. 31, 2023
Stockholders' Equity Note [Abstract]
Shareholders' Equity	Shareholders’ Equity Common and preferred stock consists of the following: Common Stock, $1 Par Value December 2023 (Units in Millions) Common Shares Authorized 5,400 Common Shares Issued and Outstanding 1,958 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. Common Stock Split On June 4, 2021, CSX announced a three-for-one split of the Company’s common stock in the form of a stock dividend. Each shareholder of record on June 18, 2021, received two additional shares of common stock for each share held as of this record date. The new shares were distributed after close of trading on June 28, 2021. All prior period share and per share amounts, common stock, other capital, and retained earnings were retroactively adjusted to reflect the impact of the stock split. Proportional adjustments were also made to outstanding awards under the Company's stock-based compensation plans. Other Capital

Stock Plans and Share-Based Com

Stock Plans and Share-Based Compensation	12 Months Ended
Stock Plans and Share-Based Compensation	Dec. 31, 2023
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 and Talent Management Committee of the Board of Directors. Awards to the Chief Executive Officer are approved by the full Board and awards to senior executives are approved by the Compensation and Talent Management Committee. In certain circumstances, the Chief Executive Officer or delegate approves 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 and Sustainability 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. Alternatively, expense is recognized upon death or over an accelerated service period for retirement-eligible employees whose agreements allow for continued vesting upon retirement. 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. Years Ended (Dollars in Millions) 2023 2022 2021 Share-Based Compensation Expense Performance Units $ 20 $ 35 $ 71 Restricted Stock Units and Awards 19 15 12 Stock Options 12 17 18 Employee Stock Purchase Plan 7 5 4 Stock Awards for Directors 2 2 2 Total Share-based Compensation Expense $ 60 $ 74 $ 107 Income Tax Benefit $ 14 $ 17 $ 23 Long-term Incentive Plans The objective of the CSX Long-term Incentive Plans (“LTIP”) is to motivate and reward certain employees for achieving and exceeding certain financial goals. The 2023-2025, 2022-2024, and 2021-2023 LTIPs were adopted under the 2019 Stock and Incentive Award Plan. 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. NOTE 4. Stock Plans and Share-Based Compensation, continued In 2023, 2022 and 2021, target performance units were granted to certain employees under three separate LTIP plans covering three-year cycles: the 2023-2025 ("2023-2025 LTIP"), the 2022-2024 ("2022-2024 LTIP"), and the 2021-2023 ("2021-2023 LTIP"). Payouts of performance units for the plans will be based on the achievement of certain goals, in each case excluding non-recurring items as disclosed in the Company’s financial statements. • For the 2023-2025 and 2022-2024 LTIP plan, the average annual operating income growth percentage and Economic Profit (CSX Cash Earnings or CCE), in each case excluding non-recurring items as defined in the plan, will each comprise 50% of the payout and will be measured independently of the other. Participants will receive stock dividend equivalents declared over the performance period based on the number of performance units paid upon vesting. As defined under the plan, Economic Profit incentivizes strategic investments earning more than the required return and is calculated as CSX’s gross cash earnings (after-tax adjusted EBITDA) minus the long-term average cost of capital on gross operating assets. • For the 2021-2023 LTIP plan, the average annual operating income growth percentage and cumulative free cash flow over the plan period will each comprise 50% of the payout and will be measured independently of the other. Participants will receive stock dividend equivalents declared over the performance period based on the number of performance units paid upon vesting. 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 250%, based upon the Company’s total shareholder return relative to specified comparable groups over the performance period. The fair values of the performance units awarded during the years ended December 2023, 2022 and 2021 were calculated primarily using a Monte-Carlo simulation model with the following weighted-average assumptions: Years Ended Weighted-Average Assumptions Used: 2023 2022 2021 Risk-free Interest Rate 4.4 % 2.3 % 0.2 % Annualized Volatility 33.2 % 33.0 % 33.6 % Expected Life (in years) 2.8 2.7 2.9 The risk-free interest rate assumptions reflect the U.S. Treasury yield curve in effect at the time of grant. The annualized volatility is based on observed historical volatility of daily stock returns for the three-year period preceding the grant date. The expected life is calculated using the remainder of the performance period. NOTE 4. Stock Plans and Share-Based Compensation, continued Performance unit grant and vesting information is summarized as follows: Years Ended 2023 2022 2021 Weighted-Average Fair Value of Units Granted $ 31.57 $ 33.89 $ 30.11 Fair Value of Units Vested (in Millions) $ 16 $ 24 $ 19 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, 2022 1,254 $ 32.14 Granted 755 31.57 Forfeited (118) 32.20 Vested (570) 30.23 Unvested at December 31, 2023 1,321 $ 32.65 As of December 2023, there was $20 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 2023, 2022 and 2021 were primarily granted along with the corresponding LTIP plans. With these grants, 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 become exercisable in equal installments on the anniversary of the grant date over a vesting period (three-year graded). 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 option valuation 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 6.0 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). NOTE 4. Stock Plans and Share-Based Compensation, continued Assumptions and inputs used to estimate fair value of stock options are summarized as follows: Years Ended 2023 2022 2021 Weighted-Average Fair Value of Units Granted $ 9.82 $ 10.12 $ 7.94 Stock Options Valuation Assumptions: Annual Dividend Yield 1.4 % 1.1 % 1.2 % Risk-free Interest Rate 3.8 % 2.0 % 0.7 % Annualized Volatility 29.6 % 30.1 % 31.2 % Expected Life (in Years) 6.0 6.0 6.0 Other Pricing Model Inputs: Weighted-average Grant-date Market Price of CSX Stock (Strike Price) $ 31.54 $ 35.12 $ 29.65 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, 2022 13,400 $ 24.03 Granted 1,234 31.54 Forfeited (189) 32.68 Exercised (2,351) 22.06 Outstanding at December 31, 2023 12,094 $ 25.04 6.0 $ 117 Exercisable at December 31, 2023 9,239 $ 22.73 5.3 $ 111 Unrecognized compensation expense related to stock options as of December 2023 was $12 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. Additional information on stock option exercises is summarized as follows: Years Ended (Dollars in Millions) 2023 2022 2021 Intrinsic Value of Stock Options Exercised $ 27 $ 9 $ 32 Cash Received from Option Exercises $ 52 $ 15 $ 31 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 (three-year cliff) or on the annual anniversary of the grant date over a vesting period (three-year graded). Separately, restricted stock awards generally vest over an employment period of up to five years. These awards are time-based and not based upon CSX’s attainment of operational targets. Participants receive cash or stock dividend equivalents on these shares, depending on the grant. Restricted stock grant and vesting information is summarized as follows: Years Ended 2023 2022 2021 Weighted-Average Fair Value of Units Granted $ 31.46 $ 34.55 $ 29.84 Fair Value of Units and Awards Vested (in Millions) $ 8 $ 5 $ 12 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, 2022 1,552 $ 31.68 Granted 880 31.46 Forfeited (100) 31.92 Vested (303) 27.49 Unvested at December 31, 2023 2,029 $ 31.70 As of December 2023, unrecognized compensation expense for these restricted stock units and awards was approximately $28 million , which will be expensed over a weighted-average remaining period of two years. NOTE 4. Stock Plans and Share-Based Compensation, continued Stock Awards for Directors CSX’s non-management directors receive a base annual retainer of $130,000 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 $180,000 and the independent non-executive Chairman also receives an annual grant of common stock in the amount of approximately $250,000. These awards are evaluated periodically by the Board of Directors. 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 12 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 market value 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 2023, 2022 and 2021, the Company issued the following shares under this program. Years Ended 2023 2022 2021 Shares Issued (in Thousands) 959 726 730 Weighted Average Purchase Price Per Share $ 25.66 $ 25.93 $ 21.90

Casualty, Environmental and Oth

Casualty, Environmental and Other Reserves	12 Months Ended
Casualty, Environmental and Other Reserves	Dec. 31, 2023
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 31, 2020 $ 196 $ 76 $ 42 $ 314 Assumed in Acquisition of Quality Carriers — 29 33 62 Charged to Expense 55 26 49 130 Payments (71) (23) (44) (138) December 31, 2021 180 108 80 368 Assumed in Acquisition of Pan Am 19 36 — 55 Charged to Expense 45 47 51 143 Payments (50) (30) (50) (130) December 31, 2022 194 161 81 436 Charged to Expense 69 29 67 165 Payments (68) (36) (57) (161) December 31, 2023 $ 195 $ 154 $ 91 $ 440 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 2023, 2022 and 2021. Casualty, environmental and other reserves are provided for in the consolidated balance sheets as shown in the table below. December 2023 December 2022 (Dollars in Millions) Current Long-term Total Current Long-term Total Casualty: Personal Injury $ 45 $ 83 $ 128 $ 40 $ 86 $ 126 Occupational 7 60 67 10 58 68 Total Casualty $ 52 $ 143 $ 195 $ 50 $ 144 $ 194 Environmental 41 113 154 53 108 161 Other 51 40 91 41 40 81 Total $ 144 $ 296 $ 440 $ 144 $ 292 $ 436 NOTE 5. Casualty, Environmental and Other Reserves, continued 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 represent accruals for personal injury, occupational disease and occupational injury claims primarily related to railroad operations. Casualty reserves include liabilities assumed as a result of the Company's acquisition of Pan Am in 2022. The Company's self-insured retention amount for casualty claims is $100 million per occurrence. 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 purchased services and other on the consolidated income statements. 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. These analyses did not result in a material adjustment to the personal injury reserve in 2023, 2022 or 2021. NOTE 5. Casualty, Environmental and Other Reserves, continued Occupational Occupational reserves represent liabilities arising from allegations of exposure to certain materials in the workplace (such as solvents, soaps, chemicals and diesel fumes), past exposure to asbestos or allegations of chronic physical injuries resulting from work conditions (such as repetitive stress injuries). The Company retains an independent actuary to analyze the Company’s historical claims, settlement amounts, and dismissal rates to assist in determining future anticipated claim filing rates and average settlement values. This analysis is performed by the actuary and reviewed by management quarterly. There were no material adjustments to the occupational reserve in 2023, 2022 or 2021. Environmental 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 230 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. Environmental reserves include liabilities assumed as a result of the Company's acquisition of Pan Am in 2022 and Quality Carriers in 2021. 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 management's review process, amounts have been recorded 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 purchased services 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 include liabilities for various claims, such as automobile, property, general liability, workers' compensation and longshoremen disability claims. Other reserves include liabilities assumed as a result of the Company's acquisition of Pan Am in 2022 and Quality Carriers in 2021.

Properties

Properties	12 Months Ended
Properties	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Properties	Properties Details of the Company’s net properties are as follows: (Dollars in Millions) Accumulated Net Book Annual Depreciation Estimated Useful Life Depreciation December 2023 Cost Depreciation Value Rate (Avg. Years) Method Road Rail and Other Track Material $ 9,537 $ (1,978) $ 7,559 2.5% 41 Group Life Ties 7,020 (2,131) 4,889 3.5% 28 Group Life Grading 2,796 (668) 2,128 1.3% 75 Group Life Ballast 3,424 (1,119) 2,305 2.6% 38 Group Life Bridges, Trestles, and Culverts 3,121 (525) 2,596 1.7% 60 Group Life Signals and Interlockers 3,376 (1,351) 2,025 4.1% 24 Group Life Buildings 1,530 (608) 922 2.5% 40 Group Life/ Straight Line (a) Other 5,786 (2,546) 3,240 4.1% 25 Group Life/ Straight Line (a) Total Road 36,590 (10,926) 25,664 Equipment Locomotive 4,952 (1,981) 2,971 3.8% 26 Group Life Freight Cars 2,300 (378) 1,922 3.1% 32 Group Life Work Equipment and Other 3,391 (2,100) 1,291 8.9% 11 Group Life/ Straight Line (a) Total Equipment 10,643 (4,459) 6,184 Land 2,272 — 2,272 N/A N/A N/A Construction In Progress 815 — 815 N/A N/A N/A Total Properties $ 50,320 $ (15,385) $ 34,935 (a) For depreciation method, certain asset categories contain intermodal terminals, trucking 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 2022 Cost Depreciation Value Rate (Avg. Years) Method Road Rail and Other Track Material $ 8,660 $ (1,405) $ 7,255 2.5% 41 Group Life Ties 6,763 (2,010) 4,753 3.5% 28 Group Life Grading 2,741 (637) 2,104 1.3% 75 Group Life Ballast 3,383 (1,130) 2,253 2.6% 38 Group Life Bridges, Trestles, and Culverts 2,989 (454) 2,535 1.7% 60 Group Life Signals and Interlockers 3,299 (1,210) 2,089 4.1% 24 Group Life Buildings 1,416 (558) 858 2.5% 40 Group Life/ Straight Line (a) Other 5,541 (2,323) 3,218 4.1% 25 Group Life/ Straight Line (a) Total Road 34,792 (9,727) 25,065 Equipment Locomotive 4,848 (1,856) 2,992 3.8% 26 Group Life Freight Cars 2,316 (369) 1,947 3.1% 32 Group Life Work Equipment and Other 3,132 (1,911) 1,221 8.9% 11 Group Life/ Straight Line (a) Total Equipment 10,296 (4,136) 6,160 Land 2,272 — 2,272 N/A N/A N/A Construction In Progress 745 — 745 N/A N/A N/A Total Properties $ 48,105 $ (13,863) $ 34,242 (a) For depreciation method, certain asset categories contain intermodal terminals, trucking 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 United States generally accepted accounting principles ("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, which is primarily completed by CSXT employees, as well as the acquisition or construction of new assets that enable CSX to enhance its operations or provide new capacity offerings to its customers. 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 costs to modify or rebuild these assets, which 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 84% of total fixed assets of $50.3 billion on a gross basis as of December 2023. 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. Depreciation Studies 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 Surface Transportation Board ("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. The Company completed a depreciation study for its road and track assets in 2020 and for equipment assets in 2022, both of which resulted in changes to accumulated depreciation, service lives, salvage values, and other related factors for certain assets. The 2022 equipment study resulted in an increase in annual depreciation expense of approximately $80 million primarily due to deferred losses on assets depreciated using the group-life method. A depreciation study was not performed in 2023. 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 retires assets on a statistical curve relative to the age of the assets. 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 depreciation studies. No material gains or losses were recognized on the sale of assets depreciated using the group-life method in 2023, 2022 or 2021, 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 purchased services and other on the consolidated statements of income. Primarily as a result of its initiative to monetize non-core properties, the Company recognized gains on the sale of properties of $34 million, $238 million, and $454 million in 2023, 2022 and 2021, respectively. Gains in 2022 and 2021 include amounts from the Virginia transaction discussed below. Sale of Property Rights to the Commonwealth of Virginia On March 26, 2021, the Company entered into a comprehensive agreement to sell certain property rights in three CSX-owned line segments to the Commonwealth of Virginia (“Commonwealth”) over three phases. The timing and amount of gains recognized were based on the allocation of fair value to each conveyance, the timing of future conveyances and collectability. Over the course of this transaction, which was completed in 2022, total proceeds of $525 million were collected and total gains of $493 million were recognized. Gains and proceeds related to this transaction are summarized in the following table. Years Ended (Dollars in Millions) 2023 2022 2021 Gains $ — $ 144 $ 349 Proceeds — 125 400 NOTE 6. Properties, continued 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. Impairment expense of $2 million in 2023, $4 million in 2022, and $2 million in 2021 was primarily due to the discontinuation of certain in-progress projects. Impairment expense is recorded in purchased services and other expense on the consolidated income statement. Government Assistance The Company is a party to contracts with recipients and subrecipients of awards from federal, state and local governmental agencies. These contracts meet the disclosure requirements under ASU 2021-10, Disclosure by Business Entities about Government Assistance, which the Company adopted effective year end 2022. These awards are typically in the form of cash for purposes of making improvements to the rail network as part of public safety, corridor expansion or economic revitalization initiatives. The awarding agency generally specifies how the awards are to be spent by the recipients and may include limited conditions requiring return of the assistance. properties

Leases

Leases	12 Months Ended
Leases	Dec. 31, 2023
Leases [Abstract]
Leases	Leases 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, including a significant operating lease with the State of Georgia for approximately 137 miles of right-of-way with integral equipment for a term of 50 years with an annual 2.5% increase. Non-cancelable, long-term leases may include provisions for maintenance, options to purchase and options to extend the terms. These options are included in the lease term when it is reasonably certain that the option will be exercised. 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 2023, 2022 or 2021. NOTE 7. Leases, continued The following table presents information about the amount, timing and uncertainty of cash flows arising from all of the Company’s operating leases as of December 31, 2023 . (Dollars in Millions) December 2023 Maturity of Lease Liabilities Lease Payments 2024 $ 70 2025 67 2026 51 2027 43 2028 35 Thereafter 1,108 Total Undiscounted Operating Lease Payments $ 1,374 Less: Imputed Interest (815) Present Value of Operating Lease Liabilities $ 559 (Dollars in Millions) 2023 2022 Balance Sheet Classification Right of Use Asset $ 498 $ 505 Current Lease Liabilities (Included in Other Current Liabilities) $ 68 $ 69 Long-term Lease Liabilities 491 488 Total Operating Lease Liabilities $ 559 $ 557 Other Information Weighted-average Remaining Lease Term for Operating Leases 30 years 31 years Weighted-average Discount Rate for Operating Leases 5.1 % 5.0 % Cash Flows As of December 2023 and 2022, the Company's right-of-use asset was valued at $498 million and $505 million, respectively. In 2023, right of use assets of $56 million were recognized as non-cash asset additions due to new operating lease liabilities. In 2022, right-of-use assets of $74 million were recognized as non-cash asset additions due to new operating lease liabilities. Cash paid for amounts included in the present value of operating lease liabilities was $78 million and $76 million during the years ended 2023 and 2022, respectively, and is included in operating cash flows. NOTE 7. Leases, continued 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. Years Ended (Dollars in Millions) 2023 2022 2021 Rent Expense on Operating Leases $ 109 $ 109 $ 89 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 2023 or December 2022. 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 2023, 2022 or 2021.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
Commitments and Contingencies	Dec. 31, 2023
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 CSXT’s payments, including prepayments, for the long-term maintenance program which covers approximately 1,900 locomotives with payments based on active status during the period. Years Ended (a) (Dollars in Millions) 2023 2022 2021 Amounts Paid $ 200 $ 168 $ 99 (a) The 2022 amount has been updated to include prepayments of $40 million. NOTE 8. Commitments and Contingencies, continued 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, track maintenance services and materials, 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 Total 2024 $ 342 $ 182 $ 524 2025 365 137 502 2026 397 37 434 2027 521 37 558 2028 402 33 435 Thereafter 1,223 56 1,279 Total $ 3,250 $ 482 $ 3,732 Insurance The Company maintains insurance programs with substantial limits for property damage, including resulting business interruption, and third-party liability. A certain amount of risk is retained by the Company on each insurance program. Under its property insurance program, the Company retains all risk up to $100 million per occurrence for losses from floods and named windstorms and up to $75 million per occurrence for other property losses. For third-party liability claims, the Company retains all risk up to $100 million per occurrence. As CSX negotiates insurance coverage above its full self-retention amounts, it retains a percentage of risk at various layers of coverage. 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 outcomes 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 is likely to 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. NOTE 8. Commitments and Contingencies, continued The Company is able to estimate a range of possible loss for certain matters for which a loss is reasonably possible in excess of reserves established. The Company has estimated this range to be $3 million to $55 million in the aggregate as of December 31, 2023. 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 consolidated case is now moving forward without class certification. Although the class was not certified, individual shippers have since brought claims against the railroads, which have been consolidated into a separate case. 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, ("Pharmacia") 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. NOTE 8. Commitments and Contingencies, continued For the lower eight miles of the Study Area, EPA issued its Record of Decision detailing the agency’s mandated remedial process in March 2016. Occidental Chemical Corporation ("Occidental") is performing the remedial design for the lower eight-mile portion of the Study Area pursuant to a consent order with EPA. For the remaining upper nine miles of the Study Area, EPA selected an interim remedy in a Record of Decision dated September 28, 2021. On March 2, 2023, EPA issued an administrative order requiring Occidental to design the interim remedy for the upper nine miles of the Study Area. Potentially responsible parties, including Pharmacia, are participating in an EPA-directed allocation and settlement process to assign responsibility related to the lower river and the entire Study Area, respectively. CSXT participated in the EPA-directed allocation and settlement process on behalf of Pharmacia. On March 2, 2022, EPA issued a Notice Letter to Pharmacia, Occidental and eight other parties alleging they are liable under Section 107(a) of CERCLA for releases or threatened releases of hazardous substances and requesting each party, individually or collectively, submit good faith offers to EPA in connection with the entire Study Area. CSXT, on behalf of Pharmacia, responded to the Notice Letter and submitted a good faith offer to EPA on June 27, 2022, following meetings with a mediator from EPA’s Conflict Prevention and Resolution Center. On November 21, 2023, EPA notified the United States District Court for the District of New Jersey that it intended to move to enter a Consent Decree (“CD”) with a group of potentially responsible parties. On January 31, 2024, EPA filed a motion to enter a modified CD with 82 potentially responsible parties, requiring payment of $150 million to resolve their liability with respect to the entire Study Area. Pharmacia is not a participant in the CD settlement. Negotiations with EPA and other parties to resolve Pharmacia's liability continue. CSXT is also defending and indemnifying Pharmacia with regard to the Property in litigation filed by Occidental, which is seeking to recover its past and future costs associated with the remediation of 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 a federal lawsuit filed by Occidental on June 30, 2018, and one of 37 defendants in a federal lawsuit filed by Occidental on March 24, 2023. CSXT is also defending and indemnifying Pharmacia in a cooperative natural resource damages assessment process related to the Property.

Employee Benefit Plans

Employee Benefit Plans	12 Months Ended
Employee Benefit Plans	Dec. 31, 2023
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 between 2003 and 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. The CSX Pension Plan, the largest plan based on benefit obligation, was closed to new participants beginning in 2020. 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 . As of Pension Plan Participants: January 1, 2023 Active Employees 2,479 Retirees and Beneficiaries 11,294 Other (a) 3,504 Total 17,277 (a) The Other category consists mostly of terminated but vested former employees. NOTE 9. Employee Benefit Plans, continued The benefit obligation for these plans represents the liability of the Company for current and former 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 nonqualified pension benefits on a pay-as-you-go basis. No qualified pension plan contributions were made during 2023, 2022 and 2021. No contributions to the Company's qualified pension plans are expected in 2024. Future expected benefit payments are as follows: Expected Cash Flows (Dollars in Millions): Pension Benefits 2024 $ 190 2025 186 2026 183 2027 182 2028 181 2029-2033 870 Total $ 1,792 Plan Assets The Company outsources investment management related to pension plan assets. The CSX Investment Committee (the “Investment Committee”), whose members are selected by the Executive Vice President and Chief Financial Officer, is responsible for setting policy and oversight of investment management. The Investment Committee and investment manager utilize 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. NOTE 9. Employee Benefit Plans, continued The current asset allocation targets 55% growth-oriented investments and 45% immunizing investments. The growth-oriented portfolio consists of return-seeking investments that are diversified across geography, market capitalization, and asset class. The immunizing portfolio is comprised of a customized mix of fixed income and cash investments designed to reduce liability risk. Allocations are evaluated for levels within 5% 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 2023 December 2022 Percent of Percent of (Dollars in Millions) Amount Total Assets Amount Total Assets Equity $ 1,142 47 % $ 1,249 54 % Fixed Income 114 4 144 6 Cash and Cash Equivalents 15 1 41 2 Growth-Oriented $ 1,271 52 % $ 1,434 62 % Fixed Income 911 38 777 33 Cash and Cash Equivalents 240 10 116 5 Immunizing $ 1,151 48 % $ 893 38 % Total $ 2,422 100 % $ 2,327 100 % Under the supervision of the Investment Committee, the investment manager selects investments or fund managers 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 can 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 2023 and 2022 plan years are as follows: Pension Benefits Plan Year Plan Year (Dollars in Millions) 2023 2022 Actuarial Present Value of Benefit Obligation Accumulated Benefit Obligation $ 2,252 $ 2,285 Projected Benefit Obligation 2,343 2,368 Change in Projected Benefit Obligation: Projected Benefit Obligation at Beginning of Plan Year $ 2,368 $ 3,022 Service Cost (a) 28 36 Interest Cost 111 64 Actuarial Loss (Gain) 20 (570) Benefits Paid (184) (184) Benefit Obligation at End of Plan Year $ 2,343 $ 2,368 Change in Plan Assets: Fair Value of Plan Assets at Beginning of Plan Year $ 2,327 $ 3,016 Actual Return (Loss) on Plan Assets 259 (523) Non-qualified Employer Contributions 20 18 Benefits Paid (184) (184) Fair Value of Plan Assets at End of Plan Year $ 2,422 $ 2,327 Funded Status at End of Plan Year $ 79 $ (41) (a) Service cost for 2023 and 2022 includes capitalized service costs of $4 million each year. In 2023, the $20 million net actuarial loss for pension benefits was driven by a 20 basis point decrease in the weighted average discount rate, partially offset by changes to census data. The $570 million net actuarial gain for pension benefits in 2022 was driven by a 224 basis point increase in the weighted average discount rate. 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 plan by recording a liability (underfunded plan) or asset (overfunded plan) for the difference between the projected benefit obligation and the fair value of plan assets at the plan measurement date. Amounts related to pension 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 December December (Dollars in Millions) 2023 2022 Amounts Recorded in Consolidated Balance Sheets: Long-term Assets $ 277 $ 164 Current Liabilities (16) (17) Long-term Liabilities (182) (188) Net Amount Recognized in Consolidated Balance Sheets $ 79 $ (41) Long-term assets as of December 2023 and 2022 in the preceding table relate to qualified pension plans where assets exceed projected benefit obligations. Current and long-term liabilities relate to plans where projected benefits obligations exceed assets. The following table shows the value of plan assets for only those plans with a net liability status. Aggregate (Dollars in Millions) Fair Value Aggregate Benefit Obligations in Excess of Plan Assets of Plan Assets Benefit Obligation Projected Benefit Obligation $ — $ (198) Accumulated Benefit Obligation — (188) 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. The following table describes the components of expense/(income) related to net benefit expense recorded on the income statement. Pension Benefits (Dollars in Millions) 2023 2022 2021 Service Cost Included in Labor and Fringe $ 24 $ 32 $ 41 Interest Cost 111 64 55 Expected Return on Plan Assets (164) (188) (186) Amortization of Net Loss 29 50 73 Total Income Included in Other Income - Net $ (24) $ (74) $ (58) Net Periodic Benefit Cost (Credit) $ — $ (42) $ (17) Settlement Loss — 1 — Total Periodic Benefit Cost (Credit) $ — $ (41) $ (17) Pension 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 benefits. (Dollars in Millions) Pension Benefits Components of Other Comprehensive Years Ended Loss (Income) 2023 2022 Recognized in the Balance Sheet (Gains) Losses $ (75) $ 141 Expense Recognized in the Income Statement Amortization of Net Losses $ 29 $ 50 Settlement Loss — 1 As of December 2023, the balance to be amortized related to the Company's pension obligations is a pre-tax loss of $623 million. This amount is included in accumulated other comprehensive loss, a component of shareholders’ equity. NOTE 9. Employee Benefit Plans, continued 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, with the assistance of the outsourced investment manager, balances market expectations obtained from various investment managers 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 benefits expense by using individual spot rates matched with separate cash flows for each future year. The weighted averages of assumptions used by the Company to value its pension obligations were as follows: Pension Benefits 2023 2022 Expected Long-term Return on Plan Assets: Benefit Cost for Current Plan Year 6.75 % 6.75 % Benefit Cost for Subsequent Plan Year 6.75 % 6.75 % Discount Rates: Benefit Cost for Plan Year Service Cost for Plan Year 5.09 % 2.98 % Interest Cost for Plan Year 4.90 % 2.18 % Benefit Obligation at End of Plan Year 4.82 % 5.02 % Salary Scale Inflation 4.80 % 4.80 % Cash Balance Plan Interest Credit Rate 3.75 % 3.75 % NOTE 9. Employee Benefit Plans, continued Post-retirement Medical Plan 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. The accumulated post-retirement benefit obligation related to this plan was $56 million and $61 million, respectively, as of December 31, 2023 and 2022. Through 2033, total future expected benefit payments related to this plan were $50 million. Expenses in 2023, 2022 and 2021 related to this plan were not material. 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 $11 million, $13 million and $21 million in 2023, 2022 and 2021, 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 $35 million, $28 million and $29 million for 2023, 2022 and 2021, respectively, and is included in labor and fringe expense on the consolidated income statement. Under the terms of collective bargaining agreements that cover union-represented employees, Quality Carriers contributes to two multi-employer pension plans. These plans provide defined benefits to retired participants. Both of these pension plans are in Pension Protection Act zone “red”, meaning they are at least 65% underfunded. Formal rehabilitation plans have been adopted. Based on information provided to the Company from the administrators of these plans, Quality Carriers’ portion of the contingent liability in the event of a full withdrawal or termination from these plans is estimated to be approximately $334 million. Of this amount, $328 million relates to the Central States Southeast and Southwest Areas Pension Plan and is based on information as of December 31, 2022, which is the latest information available at the date the financial statements were issued. The Company does not currently intend to withdraw from any of these multi-employer pension plans. Required monthly contributions to these plans are not material.

Debt and Credit Agreements

Debt and Credit Agreements	12 Months Ended
Debt and Credit Agreements	Dec. 31, 2023
Debt Disclosure [Abstract]
Debt and Credit Agreements	Debt and Credit Agreements Debt at December 2023 and December 2022 is shown in the table below. For information regarding the fair value of debt, see Note 13, Fair Value Measurements . Maturity at Average December December (Dollars in Millions) 2023 2023 2023 2022 Notes 2024-2068 4.2% $ 18,514 $ 17,877 Equipment Obligations (a) 2024-2027 4.4% 2 141 Finance Leases 2024-2032 5.9% 17 29 Subtotal Long-term Debt (Including Current Portion) $ 18,533 $ 18,047 Less Debt Due within One Year (558) (151) Long-term Debt (Excluding Current Portion) $ 17,975 $ 17,896 (a) Equipment obligations are secured by an interest in certain railroad equipment. Debt Issuance & Early Redemption of Long-term Debt On September 7, 2023, CSX issued $600 million of 5.20% notes due 2033. These notes 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. In July 2022, CSX issued $950 million aggregate principal amount of 4.10% notes due 2032, $900 million aggregate principal amount of 4.50% notes due 2052 and $150 million aggregate principal amount of 4.65% notes due 2068. The 2068 notes are a reopening of existing notes originally issued in February 2018. These notes 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. In July 2021, finance lease obligations and debt totaling $68 million were assumed related to the Company's acquisition of Quality Carriers on July 1, 2021. No debt was issued in 2021. The net proceeds from debt issuances will be used for general corporate purposes, which may include debt repayments, repurchases of CSX’s common stock, capital investment and working capital requirements. For more information regarding a non-cash debt transaction with a related party, see Note 15, Investment in Affiliates and Related-Party Transactions . NOTE 10. Debt and Credit Agreements, continued Long-term Debt Maturities (Net of Discounts, Premiums and Issuance Costs) (Dollars in Millions) Maturities at Years Ending December 2023 2024 $ 558 2025 606 2026 704 2027 998 2028 1,001 Thereafter 14,666 Total Long-term Debt Maturities, including current portion $ 18,533 Interest Rate Derivatives Fair Value Hedges In fourth quarter 2023, CSX entered into two separate fixed-to-floating interest rate swaps classified as fair value hedges. The swaps are designed to hedge 10 years of interest rate risk associated with market fluctuations attributable to the Secured Overnight Financing Rate ("SOFR") on a cumulative $250 million of fixed rate outstanding notes which are due in 2033. The cumulative fair value of these swaps, which is included in other long-term assets on the consolidated balance sheet, was an asset of $19 million as of December 31, 2023. In first quarter 2022, CSX entered into five separate fixed-to-floating interest rate swaps classified as fair value hedges. The swaps are designed to hedge 10 years of interest rate risk associated with market fluctuations attributable to the SOFR on a cumulative $800 million of fixed rate outstanding notes which are due between 2036 and 2040. The cumulative fair value of these swaps which is included in other long-term liabilities on the consolidated balance sheet, was a liability of $107 million and $118 million as of December 31, 2023, and December 31, 2022, respectively. The 2022 swaps will expire in 2032 and the 2023 swaps will expire in 2033. If settled early, the remaining cumulative fair value adjustment to the hedged notes will be amortized over the remaining life of the associated notes. The cumulative adjustment to the hedged notes is included in long-term debt on the consolidated balance sheet as shown in the following table. (Dollars in Millions) December 31, 2023 December 31, 2022 Notional Value of Hedged Notes $ 1,050 $ 800 Fair Value Asset Adjustment to Hedged Notes 19 — Fair Value Liability Adjustment to Hedged Notes (107) (118) Carrying Amount of Hedged Notes $ 962 $ 682 NOTE 10. Debt and Credit Agreements, continued Gains and losses resulting from changes in fair value of the interest rate swaps offset changes in the fair value of the hedged portion of the underlying debt with no gain or loss recognized due to hedge ineffectiveness. The difference in the net fixed-to-float interest settlement on the derivatives is recognized in interest expense and is summarized as follows. (Dollars in Millions) 2023 2022 2021 Interest Expense Impact (Increase) Decrease $ (28) $ (1) N/A Cash Flow Hedges In 2020, the Company executed forward starting interest rate swaps, classified as cash flow hedges, with aggregate notional value of $500 million. These swaps were effected to hedge the benchmark interest rate associated with future interest payments related to the anticipated refinancing of $850 million of 3.25% notes due in 2027. In accordance with the Derivatives and Hedging Topic in the ASC, the Company has designated these swaps as cash flow hedges. Under the terms of the Adjustable Interest Rate (LIBOR) Act, the reference rate on the swaps were automatically replaced with daily compounded SOFR plus the fallback spread on July 1, 2023, the LIBOR replacement date. In fourth quarter 2022, CSX settled a portion equal to $160 million notional value of the aggregate $500 million cash flow hedges, which resulted in CSX receiving a cash payment of $52 million included in other operating activities on the consolidated cash flow statement. In second quarter 2023, CSX executed a partial settlement equal to $113 million notional value of the cash flow hedges, which resulted in CSX receiving a cash payment of $44 million. In third quarter 2023, CSX partially settled an additional $113 million notional value of the cash flow hedges and received a cash payment of $51 million included in other operating activities on the consolidated cash flow statement. The unsettled aggregate notional value of these swaps was $114 million and $340 million as of December 31, 2023, and December 31, 2022, respectively. As of December 31, 2023 and 2022, the asset value of the forward starting interest rate swaps was $48 million and $127 million, respectively, and was recorded in other long-term assets on the consolidated balance sheet. Unrealized gains or losses associated with changes in the fair value of the hedge are recorded net of tax in accumulated other comprehensive income (“AOCI”) on the consolidated balance sheet. The unrealized gain associated with the settled portion of the hedges will continue to be classified in AOCI until the associated debt instrument is issued in the future. Unless settled early, the remainder of the swaps will expire in 2027 and the unrealized gain or loss in AOCI will be recognized in earnings as an adjustment to interest expense over the same period during which the hedged transaction affects earnings. Unrealized amounts related to the hedge, recorded net of tax in other comprehensive income, are summarized in the table below. (Dollars in Millions) 2023 2022 2021 Unrealized Gain - Net $ — $ 80 $ 8 See Note 13, Fair Value Measurements , and Note 16, Other Comprehensive Income (Loss) , for other information about the Company's hedges. NOTE 10. Debt and Credit Agreements, continued Credit Facilities In February 2023, CSX replaced its existing $1.2 billion unsecured revolving credit facility with a new $1.2 billion unsecured, revolving credit facility backed by a diverse syndicate of banks. This facility allows same-day borrowings at floating interest rates, based on SOFR or an agreed-upon replacement reference rate, plus a spread that depends upon CSX's senior unsecured debt ratings. This facility expires in February 2028. As of December 31, 2023, 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, 2023, CSX was in compliance with all covenant requirements under the facility. Commercial Paper

Revenues

Revenues	12 Months Ended
Revenues	Dec. 31, 2023
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. Years Ended (Dollars in Millions) 2023 2022 2021 Chemicals $ 2,599 $ 2,584 $ 2,421 Agricultural and Food Products 1,657 1,664 1,461 Automotive 1,219 1,054 886 Forest Products 1,012 996 918 Metals and Equipment 917 828 796 Minerals 733 658 587 Fertilizers 516 455 470 Total Merchandise 8,653 8,239 7,539 Coal 2,484 2,434 1,790 Intermodal 2,060 2,306 2,039 Trucking (a) 882 966 410 Other 578 908 744 Total $ 14,657 $ 14,853 $ 12,522 (a) Effective third quarter 2021, Trucking revenue is comprised of revenue from the operations of Quality Carriers, which was acquired by CSX effective July 1, 2021. Revenue Recognition The Company generates revenue from rail 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. NOTE 11. Revenues, continued The average transit time to complete a rail shipment is between 2 to 7 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. 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, which 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. Effective third quarter 2021, trucking revenue includes revenue from the operations of Quality Carriers and is mostly comprised of truck shipments of chemicals. A performance obligation arises when Quality Carriers receives a customer order to transport a commodity at a contracted rate. Revenue is recorded on a gross basis ratably over transit time. Other revenue is recorded upon completion of the service and is comprised of revenue from regional subsidiary railroads and incidental charges, including demurrage, intermodal storage and equipment usage, and switching. 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. Intermodal storage represents charges for customer storage of containers at an intermodal terminal, ramp facility or offsite location beyond a specified period of time. Switching represents charges assessed when a railroad switches cars for a customer or another railroad. During 2023, 2022 and 2021, revenue recognized from performance obligations related to prior periods was not material. NOTE 11. Revenues, continued 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, 2023, 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, 2023, and December 31, 2022, were not material. The Company’s accounts receivable - net consists of freight and non-freight receivables, reduced by an allowance for credit losses. (Dollars in Millions) December 31, December 31, Freight Receivables $ 1,047 $ 1,067 Freight Allowance for Credit Losses (18) (16) Freight Receivables, net 1,029 1,051 Non-Freight Receivables 378 279 Non-Freight Allowance for Credit Losses (14) (17) Non-Freight Receivables, net 364 262 Total Accounts Receivable, net $ 1,393 $ 1,313 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 credit losses to provide for the estimated amount of receivables that will not be collected. The allowance is based upon an assessment of risk characteristics, historical payment experience, and the age of outstanding receivables adjusted for forward-looking economic conditions as necessary. Credit losses recognized on the Company’s accounts receivable were not material in 2023 and 2022.

Income Taxes

Income Taxes	12 Months Ended
Income Taxes	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Earnings before income taxes of $4.9 billion, $5.4 billion and $5.0 billion for years ended 2023, 2022 and 2021, respectively, represent earnings from domestic operations. The breakdown of income tax expense between current and deferred is as follows: Years Ended (Dollars in Millions) 2023 2022 2021 Current: Federal $ 852 $ 928 $ 827 State 184 203 176 Subtotal Current $ 1,036 $ 1,131 $ 1,003 Deferred: Federal 122 166 166 State 18 (49) 1 Subtotal Deferred $ 140 $ 117 $ 167 Total Income Tax Expense $ 1,176 $ 1,248 $ 1,170 The Company recorded a 2023 income tax benefit of $22 million primarily from a change in the valuation of deferred taxes as a result of filing the 2022 tax returns. In 2022, the Company recorded an income tax benefit of $78 million primarily as a result of state legislative changes and a change in the valuation of deferred taxes as a result of filing the 2021 tax returns. In 2021, the Company recorded an income tax benefit of $48 million primarily as a result of favorable state legislative changes, additional tax benefits associated with the vesting of share-based awards and adjustments to deferred taxes as a result of filing the 2020 state tax returns. Income tax expense reconciled to the tax computed at statutory rates is presented in the following table. Years Ended (Dollars in Millions) 2023 2022 2021 Federal Income Taxes $ 1,027 21.0 % $ 1,137 21.0 % $ 1,040 21.0 % State Income Taxes 153 3.1 % 121 2.2 % 139 2.8 % Other (4) (0.1) % (10) (0.1) % (9) (0.2) % Income Tax Expense/ Rate $ 1,176 24.0 % $ 1,248 23.1 % $ 1,170 23.6 % 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: 2023 2022 (Dollars in Millions) Assets Liabilities Assets Liabilities Other Employee Benefit Plans $ 103 $ — $ 105 $ — Accelerated Depreciation — 7,678 — 7,600 Other 459 630 553 627 Total $ 562 $ 8,308 $ 658 $ 8,227 Net Deferred Income Tax Liabilities $ 7,746 $ 7,569 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 2023, 2022, and 2021. Federal examinations of original federal income tax returns for all years through 2020 are resolved. As of December 2023 and 2022, the Company had approximately $19 million and $18 million, respectively, of total unrecognized tax benefits as a result of uncertain tax positions. Net tax benefits of $15 million and $14 million as of December 2023 and 2022, respectively, could favorably impact the effective income tax rate in each year. The Company does not expect that unrecognized tax benefits as of December 2023 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 year ended December 2023.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
Fair Value Measurements	Dec. 31, 2023
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, long-term debt and interest rate derivatives. 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, long-term debt and interest rate derivatives. 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 are carried at fair value on the consolidated balance sheet in accordance with the Fair Value Measurements and Disclosures Topic in the ASC. They are valued with assistance from a third-party trustee and consist of fixed income mutual funds, corporate bonds and government securities. The fixed income mutual funds are valued at the net asset value of shares held based on quoted market prices determined in an active market, which are Level 1 inputs. The corporate bonds and government securities are valued using broker quotes that utilize observable market inputs, which are Level 2 inputs. Unrealized losses as of December 31, 2023 and December 31, 2022 were not material. The Company believes any impairment of investments held with gross unrealized losses to be temporary and not the result of credit risk. 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. December 2023 December 2022 (Dollars in Millions) Level 1 Level 2 Total Level 1 Level 2 Total Fixed Income Mutual Funds $ 80 $ — $ 80 $ 89 $ — $ 89 Corporate Bonds — 60 60 — 49 49 Government Securities — 41 41 — 58 58 Total Investments at Fair Value $ 80 $ 101 $ 181 $ 89 $ 107 $ 196 Total Investments at Amortized Cost $ 184 $ 201 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 2023 December 2022 Less than 1 year $ 83 $ 129 1 - 5 years 37 24 5 - 10 years 17 10 Greater than 10 years 44 33 Total investments at fair value $ 181 $ 196 Long-term Debt Long-term debt, which includes finance leases, 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 instrument, 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 2023 December 2022 Long-term Debt (Including Current Maturities): Fair Value $ 17,528 $ 16,135 Carrying Value 18,533 18,047 Interest Rate Derivatives The Company’s fixed-to-floating and forward starting interest rate swaps are carried at their respective fair values, which are determined with assistance from a third party based upon pricing models using inputs observed from actively quoted markets. All of the inputs used to determine the fair value of the swaps are Level 2 inputs. The fair value of the Company’s fixed-to-floating interest rate swaps was an asset of $19 million (for swaps entered in 2023) and a liability of $107 million (for swaps entered in 2022) at December 31, 2023. As of December 31, 2022, the fair value of the fixed-to-floating interest rate swaps was a liability of $118 million. The fair value of the Company’s forward starting interest rate swaps asset was $48 million and $127 million at December 31, 2023 and 2022, respectively. See Note 10, Debt and Credit Agreements, for further information. Pension Plan Assets Pension plan assets are reported at fair value, net of pension liabilities, on the consolidated balance sheet. See Note 9, Employee Benefit Plans, for further information. 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. NOTE 13. Fair Value Measurements, continued 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 varying redemption restrictions, but most require advanced notice of at least 15 business days. • Commingled and common collective trust funds: This class consists of private funds that invest in corporate equity and debt securities, government 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 45 business days. The pension plan assets at fair value by level, within the fair value hierarchy, as of calendar plan years 2023 and 2022 are shown in the table below. For additional information related to pension assets, see Note 9, Employee Benefit Plans . December 2023 December 2022 (Dollars in Millions) Level 1 Level 2 Total Level 1 Level 2 Total Common Stock $ 340 $ — $ 340 $ 335 $ — $ 335 Mutual Funds 32 — 32 29 — 29 Cash and Cash Equivalents 255 — 255 157 — 157 Corporate Bonds — 646 646 — 647 647 Government Securities — 126 126 — 88 88 Asset-backed Securities, Derivatives and Other — 10 10 — 9 9 Total Investments in the Fair Value Hierarchy $ 627 $ 782 $ 1,409 $ 521 $ 744 $ 1,265 Investments Measured at Net Asset Value (a) n/a n/a $ 1,013 n/a n/a $ 1,062 Investments at Fair Value $ 627 $ 782 $ 2,422 $ 521 $ 744 $ 2,327

Other Income - Net

Other Income - Net	12 Months Ended
Other Income - Net	Dec. 31, 2023
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. For discussion of the drivers of changes in net periodic pension and post-retirement benefit credit from 2022 to 2023 and from 2021 to 2022, refer to Note 9, Employee Benefit Plans . Interest income increased from 2022 to 2023 and from 2021 to 2022 primarily as a result of higher average interest rates. Other income – net consisted of the following: Years Ended (Dollars in Millions) 2023 2022 2021 Net Periodic Pension and Post-retirement Benefit Credit (a) $ 29 $ 79 $ 64 Interest Income 79 42 7 Miscellaneous Income 31 12 8 Total Other Income - Net $ 139 $ 133 $ 79

Investment in Affiliates and Re

Investment in Affiliates and Related-Party Transactions	12 Months Ended
Investment in Affiliates and Related-Party Transactions	Dec. 31, 2023
Related Party Transactions [Abstract]
Investment in Affiliates and Related-Party Transactions	Investment in Affiliates and Related-Party Transactions CSX's investments in affiliates are included on the consolidated balance sheet as investments in affiliates and other companies. December December (Dollars in Millions) 2023 2022 Conrail $ 1,175 $ 1,124 TTX 961 914 Other Equity Method and Cost Method Investments 261 254 Total $ 2,397 $ 2,292 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. 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 purchased services 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 2024 $ 32 2025 32 2026 32 2027 32 2028 32 Thereafter 13 Total $ 173 Also, included in equity earnings of affiliates are CSX’s 42% 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 $323 million as of December 2023. NOTE 15. Investment in Affiliates and Related-Party Transactions, continued The following table discloses amounts related to Conrail. All amounts in the table below are included in purchased services and other expenses on the Company’s consolidated income statements. Years Ended (Dollars in Millions) 2023 2022 2021 Rents, Fees and Services $ 132 $ 130 $ 128 Purchase Price Amortization and Other 4 4 4 Equity Earnings of Conrail (54) (44) (44) Total Conrail Expense $ 82 $ 90 $ 88 As required by the Related Party Disclosures Topic in the ASC, the Company has disclosed 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. In December 2020, the Company completed a non-cash conversion of $224 million of 2.89% notes due 2044 as well as its existing payable balance of approximately $217 million into new notes. The new notes for operation of the shared asset area are $441 million, 1.31% notes due 2050. Interest expense from these promissory notes was $6 million in each 2023, 2022 and 2021. December December (Dollars in Millions) 2023 2022 Balance Sheet Information: CSX Accounts Payable to Conrail $ 154 $ 136 Promissory Notes Payable to Conrail Subsidiary 1.31% CSX Promissory Note due December 2050 73 73 1.31% CSXT Promissory Note due December 2050 368 368 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. Pursuant to the Investments - Equity Method Topic in the ASC, CSX applies the equity method of accounting to its investment in TTX. As part of the Pan Am acquisition in June 2022, CSX acquired an immaterial amount of TTX stock, which was subsequently repurchased by TTX in December 2022. NOTE 15. Investment in Affiliates and Related-Party Transactions, continued As required by the Related Party Disclosures Topic in the ASC, the following table discloses amounts related to TTX. Car hire rents and equity earnings are included in equipment and other rents expense on the Company’s consolidated income statement. Years Ended (Dollars in Millions) 2023 2022 2021 Income Statement Information: Car Hire Rents $ 249 $ 241 $ 221 Equity Earnings of TTX (49) (51) (52) Total TTX Expense $ 200 $ 190 $ 169 Also included below is balance sheet information related to CSX's payable to TTX, which represents car rental liabilities. (Dollars in Millions) December December Balance Sheet Information: 2023 2022 CSX Payable to TTX $ 43 $ 38

Other Comprehensive Income (Los

Other Comprehensive Income (Loss)	12 Months Ended
Other Comprehensive Income (Loss)	Dec. 31, 2023
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 as well as derivative activity and other adjustments. Total comprehensive earnings represent the activity for a period net of tax and were $3.8 billion, $4.2 billion and $4.0 billion for 2023, 2022 and 2021, respectively. While total comprehensive earnings is the activity in a period and is largely driven by net earnings in that period, 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, interest rate derivatives and CSX's share of AOCI of equity method investees. NOTE 16. Other Comprehensive Income (Loss), continued 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. Interest rate derivatives consist of forward starting interest rate swaps classified as cash flow hedges. See Note 10, Debt and Credit Agreements, for further information. Items classified as other primarily represent CSX's share of AOCI of equity method investees. Amounts reclassified in other to net earnings are included in purchased services and other or equipment and other rents on the consolidated income statements. Pension and Other Post-Employment Benefits Interest Rate Derivatives Other Accumulated Other Comprehensive (Loss) Income (Dollars in Millions) Balance December 31, 2020 - Net of Tax $ (598) $ 62 $ (62) $ (598) Other Comprehensive Income (Loss) Income Before Reclassifications 147 11 — 158 Amounts Reclassified to Net Earnings 66 — 15 81 Tax Expense (46) (3) — (49) Total Other Comprehensive Income $ 167 $ 8 $ 15 $ 190 Balance December 31, 2021 - Net of Tax $ (431) $ 70 $ (47) $ (408) Other Comprehensive Income (Loss) (Loss) Income Before Reclassifications (129) 88 — (41) Amounts Reclassified to Net Earnings 44 — 2 46 Tax Benefit (Expense) 19 (8) 4 15 Total Other Comprehensive (Loss) Income $ (66) $ 80 $ 6 $ 20 Balance December 31, 2022 - Net of Tax $ (497) $ 150 $ (41) $ (388) Other Comprehensive Income (Loss) Income Before Reclassifications 75 16 — 91 Amounts Reclassified to Net Earnings 18 — 5 23 Tax Expense (19) (16) (3) (38) Total Other Comprehensive Income $ 74 $ — $ 2 $ 76 Balance December 31, 2023 - Net of Tax $ (423) $ 150 $ (39) $ (312)

Business Combinations

Business Combinations	12 Months Ended
Business Combinations	Dec. 31, 2023
Business Combination and Asset Acquisition [Abstract]
Business Combinations	Business Combinations Acquisition of Pan Am Systems, Inc. On June 1, 2022, CSX completed its acquisition of Pan Am Systems, Inc. (“Pan Am”), which is the parent company of Pan Am Railways, Inc. who jointly owns Pan Am Southern, LLC with a subsidiary of Norfolk Southern Corporation. Pan Am owns and operates a highly integrated, nearly 1,200-mile rail network and has a joint interest in the more than 600-mile Pan Am Southern system. This acquisition expands CSX’s reach in the Northeastern United States. The results of Pan Am's operations and its cash flows were consolidated prospectively. The Company accounted for the transaction using the acquisition method in accordance with ASC Topic 805, Business Combinations . The purchase price allocation was finalized as of December 31, 2022, and total measurement period adjustments to the preliminary allocation were immaterial. The closing price of $600 million was funded through a combination of common stock valued at $422 million and cash totaling $178 million. Cash payments are included in investing activities on the Company's consolidated cash flow statement. Total cash consideration paid to acquire the business includes a $30 million deposit paid in 2020. The allocation of total consideration to the fair values of the acquired assets and liabilities of Pan Am is summarized in the table below. (Dollars in Millions) June 1, 2022 Assets Acquired: Accounts Receivable, net $ 46 Properties and Equipment, net 600 Goodwill 17 Investments in Affiliates 90 Other Assets 11 Total Assets Acquired $ 764 Liabilities Assumed: Accounts Payable and Accrued Liabilities $ 32 Deferred Tax Liabilities 75 Other Long-term Liabilities 57 Total Liabilities Assumed $ 164 Fair Value of Assets Acquired, Net of Liabilities Assumed: $ 600 Properties and equipment of $600 million include road and track assets, work equipment, land, buildings and other assets. The investments in affiliates includes the interest in Pan Am Southern, LLC acquired as part of the purchase as well as other investments. NOTE 17. Business Combinations, continued The Company incurred costs related to this acquisition of approximately $32 million, of which $22 million was incurred in 2022 and $10 million was incurred in 2021. All acquisition-related costs were expensed as incurred and have been recorded in labor and fringe or purchased services and other in the accompanying consolidated income statements. This acquisition is not material or significant with respect to the Company’s financial statements when reviewed under the quantitative and qualitative considerations of Regulation S-X Article 11 and ASC Topic 805 . As the acquisition is not material or significant, CSX has not provided pro forma information relating to the pre-acquisition period. Acquisition of Quality Carriers, Inc. On July 1, 2021, the Company completed its acquisition of Quality Carriers, the largest provider of bulk liquid chemicals truck transportation in North America, for $544 million in cash, which is presented on the statement of cash flows net of $3 million cash acquired. Through a network of over 100 company-owned and affiliate terminals and facilities in key locations throughout the United States, Canada and Mexico, Quality Carriers provides transportation services to many of the leading chemical producers and shippers in North America. The results of Quality Carriers' operations and its cash flows were consolidated prospectively. The Company accounted for the transaction using the acquisition method in accordance with ASC Topic 805, Business Combinations . The purchase price allocation was finalized as of December 31, 2021, and total measurement period adjustments to the preliminary allocation were immaterial. The allocation of total consideration to the fair values of the acquired assets and liabilities of Quality Carriers is summarized in the table below. (Dollars in Millions) July 1, 2021 Assets Acquired: Cash and Cash Equivalents $ 3 Accounts Receivable, net 113 Properties and Equipment, net 225 Goodwill 213 Intangible Assets 180 Other Assets 9 Total Assets Acquired $ 743 Liabilities Assumed: Accounts Payable and Accrued Liabilities $ 48 Finance Lease Obligations and Notes Payable 68 Casualty, Environmental and Other Reserves 62 Other Long-term Liabilities 21 Total Liabilities Assumed $ 199 Fair Value of Assets Acquired, Net of Liabilities Assumed: $ 544 NOTE 17. Business Combinations, continued Cash paid to acquire the business, net of acquired cash and cash equivalents of $3 million, is included in investing activities on the Company's consolidated statement of cash flows. Properties and equipment of $225 million include tractors and trailers, equipment, land, buildings and other assets. For information about goodwill and intangible assets, see Note 18, Goodwill and Other Intangible Assets . In 2021, the Company incurred costs related to this acquisition of approximately $17 million. All acquisition-related costs were expensed as incurred and have been recorded in purchased services and other in the accompanying consolidated income statements. This acquisition is not material or significant with respect to the Company’s financial statements when reviewed under the quantitative and qualitative considerations of Regulation S-X Article 11 and ASC Topic 805 . As the acquisition is not material or significant, CSX has not provided pro forma information relating to the pre-acquisition period. Other Acquisitions During 2023 and 2022, Quality Carriers completed several acquisitions of previous independent affiliates that were immaterial individually and in the aggregate.

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	12 Months Ended
Goodwill and Other Intangible Assets	Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets The following table presents goodwill and other intangible asset balances and adjustments to those balances for the years ended December 31, 2023 and 2022: Goodwill Intangible Assets (Dollars in Millions) Net Carrying Amount Cost Accumulated Amortization Net Carrying Amount Total Goodwill and Other Intangible Assets - Net Balance at December 31, 2021 $ 276 $ 180 $ (5) $ 175 $ 451 Additions 43 18 — 18 61 Amortization — — (10) (10) (10) Balance at December, 31, 2022 $ 319 $ 198 $ (15) $ 183 $ 502 Additions 6 8 — 8 14 Amortization — — (10) (10) (10) Balance at December, 31, 2023 $ 325 $ 206 $ (25) $ 181 $ 506 As a result of the acquisition of Pan Am on June 1, 2022, CSX recognized $17 million of goodwill. The goodwill was calculated as the excess of the consideration paid over the fair value of net assets assumed and relates primarily to the ability of CSX to extend the reach of its service to a wider customer base over an expanded territory, creating new market prospects and efficiencies. Goodwill recognized in this acquisition is not deductible for tax purposes. During 2023 and 2022, Quality Carriers completed several acquisitions that were immaterial individually and in aggregate. The acquisitions resulted in the addition of $6 million and $26 million of goodwill in 2023 and 2022, respectively. Other intangible assets recognized as part of these acquisitions were $8 million and $18 million in 2023 and 2022, respectively. The Company's intangible assets balance primarily relates to intangibles recognized as part of the acquisition of Quality Carriers in 2021. Intangible assets recognized from the acquisition of $180 million consist of $150 million of customer relationships and $30 million of trade names that will be amortized over a weighted-average period of 20 years and 15 years, respectively. During the fourth quarter 2023, the Company changed the date of its annual assessment of Goodwill to October 1st for all reporting units. The change in testing date for goodwill is a change in accounting principle, which management believes is preferable as it will create consistency in the Company's goodwill impairment testing procedures across its reporting units. This change was not material to CSX's consolidated financial statements and it did not delay, accelerate, or avoid any potential goodwill impairment charges. No impairment was recorded as a result of the assessment.

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Millions	12 Months Ended
Pay vs Performance Disclosure - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Pay vs Performance Disclosure
Net Earnings	$ 3,715	$ 4,166	$ 3,781

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended	12 Months Ended
Insider Trading Arrangements	Dec. 31, 2023 shares	Dec. 31, 2023 shares
Trading Arrangements, by Individual
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false
Nathan D. Goldman [Member]
Trading Arrangements, by Individual
Material Terms of Trading Arrangement		On November 10, 2023, Nathan D. Goldman, Executive Vice President, Chief Legal Officer and Corporate Secretary, adopted a trading plan intended to satisfy Rule 10b5-1(c) to sell up to 83,000 shares of CSX common stock and 161,487 employee stock options to be exercised via same-day-sale on or after February 20, 2024, subject to certain conditions, to be in effect until November 8, 2024 unless otherwise terminated pursuant to the terms of the trading plan.
Name	Nathan D. Goldman
Title	Executive Vice President, Chief Legal Officer and Corporate Secretary
Rule 10b5-1 Arrangement Adopted	true
Adoption Date	November 10, 2023
Arrangement Duration	364 days
Nathan D. Goldman Trading Arrangement, Common Stock [Member] \| Nathan D. Goldman [Member]
Trading Arrangements, by Individual
Aggregate Available	83,000	83,000
Nathan D. Goldman Trading Arrangement, Employee Stock Options [Member] \| Nathan D. Goldman [Member]
Trading Arrangements, by Individual
Aggregate Available	161,487	161,487

Nature of Operations and Sign_2

Nature of Operations and Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	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, 2023 and December 31, 2022, and the consolidated statements of income, comprehensive income, cash flows and changes in shareholders’ equity for the years ended 2023, 2022 and 2021. 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.
Use of Estimates	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 and environmental reserves (see Note 5, Casualty, Environmental and Other Reserves ); • pension plan accounting (see Note 9, Employee Benefit Plans ); and • depreciation policies for assets under the group-life method (see Note 6, Properties )
Fiscal Year	Fiscal Year The Company's fiscal periods are based upon the calendar year. Except as otherwise specified, references to full years indicate CSX’s fiscal years ended on December 31, 2023, December 31, 2022, and December 31, 2021.
Principles of Consolidation	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 Affiliates and Other Companies on the consolidated balance sheets.
Cash and Cash Equivalents	Cash and Cash Equivalents
Investments	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 Materials and supplies in the consolidated balance sheets are carried at average cost 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	New Accounting Pronouncements In March 2020, the Financial Accounting Standards Board ("FASB") issued Accounting Standards Update ("ASU") 2020-04, Facilitation of the Effects of Reference Rate Reform on Financial Reporting . As the London Interbank Offered Rate ("LIBOR") is no longer available as of July 2023, this standard update provides practical expedients for contract modifications made as part of the transition from LIBOR to alternative reference rates. The guidance was effective upon issuance and at present can generally be applied through December 31, 2024. The Company applied the practical expedient to its forward starting interest rate swaps effective June 30, 2023. See Note 10, Debt and Credit Agreements , for additional information. The Company does not have any other contracts that are affected by the transition from LIBOR. In November 2023, the FASB issued ASU 2023-07, Improvements to Reportable Segment Disclosures . This standard update requires additional interim and annual disclosures about a reportable segment’s expenses, even for companies with only one reportable segment. The Company is required to adopt the guidance for its 2024 annual report filed on Form 10-K, though early adoption is permitted. The Company is currently evaluating the impact of these amendments on its disclosures, but this standard update will not impact the Company's results of operations or financial position. In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures . This standard update requires additional interim and annual disclosures about a company’s income taxes, including more detailed information around the annual rate reconciliation and income taxes paid. The Company is required to adopt the guidance for its 2025 annual report filed on Form 10-K, though early adoption is permitted. The Company is currently evaluating the impact of these amendments on its disclosures, but this standard update will not impact the Company's results of operations or financial position.
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 stock options, performance and restricted stock units. 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
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 and Talent Management Committee of the Board of Directors. Awards to the Chief Executive Officer are approved by the full Board and awards to senior executives are approved by the Compensation and Talent Management Committee. In certain circumstances, the Chief Executive Officer or delegate approves 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 and Sustainability Committee.
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 purchased services and other on the consolidated income statements. 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. These analyses did not result in a material adjustment to the personal injury reserve in 2023, 2022 or 2021. NOTE 5. Casualty, Environmental and Other Reserves, continued Occupational Occupational reserves represent liabilities arising from allegations of exposure to certain materials in the workplace (such as solvents, soaps, chemicals and diesel fumes), past exposure to asbestos or allegations of chronic physical injuries resulting from work conditions (such as repetitive stress injuries). The Company retains an independent actuary to analyze the Company’s historical claims, settlement amounts, and dismissal rates to assist in determining future anticipated claim filing rates and average settlement values. This analysis is performed by the actuary and reviewed by management quarterly. There were no material adjustments to the occupational reserve in 2023, 2022 or 2021.
Environmental Reserves	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 230 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. Environmental reserves include liabilities assumed as a result of the Company's acquisition of Pan Am in 2022 and Quality Carriers in 2021. 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 management's review process, amounts have been recorded 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 purchased services 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 United States generally accepted accounting principles ("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, which is primarily completed by CSXT employees, as well as the acquisition or construction of new assets that enable CSX to enhance its operations or provide new capacity offerings to its customers. 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 costs to modify or rebuild these assets, which 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 retires assets on a statistical curve relative to the age of the assets. 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 depreciation studies. No material gains or losses were recognized on the sale of assets depreciated using the group-life method in 2023, 2022 or 2021, 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 84% of total fixed assets of $50.3 billion on a gross basis as of December 2023. 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. Depreciation Studies
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
Leases	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, including a significant operating lease with the State of Georgia for approximately 137 miles of right-of-way with integral equipment for a term of 50 years with an annual 2.5% increase. Non-cancelable, long-term leases may include provisions for maintenance, options to purchase and options to extend the terms. These options are included in the lease term when it is reasonably certain that the option will be exercised. 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 2023, 2022 or 2021.
Revenue Recognition	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. The Company generates revenue from rail 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. NOTE 11. Revenues, continued The average transit time to complete a rail shipment is between 2 to 7 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. 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, which 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. Effective third quarter 2021, trucking revenue includes revenue from the operations of Quality Carriers and is mostly comprised of truck shipments of chemicals. A performance obligation arises when Quality Carriers receives a customer order to transport a commodity at a contracted rate. Revenue is recorded on a gross basis ratably over transit time. Other revenue is recorded upon completion of the service and is comprised of revenue from regional subsidiary railroads and incidental charges, including demurrage, intermodal storage and equipment usage, and switching. 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. Intermodal storage represents charges for customer storage of containers at an intermodal terminal, ramp facility or offsite location beyond a specified period of time. Switching represents charges assessed when a railroad switches cars for a customer or another railroad. During 2023, 2022 and 2021, revenue recognized from performance obligations related to prior periods was not material. NOTE 11. Revenues, continued 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, 2023, remaining performance obligations were not material. Contract Balances and Accounts Receivable
Allowance for Credit Losses	Freight receivables include amounts earned, billed and unbilled , and currently due from customers
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, long-term debt and interest rate derivatives. 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, long-term debt and interest rate derivatives. 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 are carried at fair value on the consolidated balance sheet in accordance with the Fair Value Measurements and Disclosures Topic in the ASC. They are valued with assistance from a third-party trustee and consist of fixed income mutual funds, corporate bonds and government securities. The fixed income mutual funds are valued at the net asset value of shares held based on quoted market prices determined in an active market, which are Level 1 inputs. The corporate bonds and government securities are valued using broker quotes that utilize observable market inputs, which are Level 2 inputs. Unrealized losses as of December 31, 2023 and December 31, 2022 were not material. The Company believes any impairment of investments held with gross unrealized losses to be temporary and not the result of credit risk. Long-term Debt Long-term debt, which includes finance leases, 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 instrument, 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. Interest Rate Derivatives The Company’s fixed-to-floating and forward starting interest rate swaps are carried at their respective fair values, which are determined with assistance from a third party based upon pricing models using inputs observed from actively quoted markets. All of the inputs used to determine the fair value of the swaps are Level 2 inputs. The fair value of the Company’s fixed-to-floating interest rate swaps was an asset of $19 million (for swaps entered in 2023) and a liability of $107 million (for swaps entered in 2022) at December 31, 2023. As of December 31, 2022, the fair value of the fixed-to-floating interest rate swaps was a liability of $118 million. The fair value of the Company’s forward starting interest rate swaps asset was $48 million and $127 million at December 31, 2023 and 2022, respectively. See Note 10, Debt and Credit Agreements, for further information. Pension Plan Assets Pension plan assets are reported at fair value, net of pension liabilities, on the consolidated balance sheet. See Note 9, Employee Benefit Plans, for further information. 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. NOTE 13. Fair Value Measurements, continued 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 varying redemption restrictions, but most require advanced notice of at least 15 business days. • Commingled and common collective trust funds:

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
Earnings Per Share (Tables)	Dec. 31, 2023
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: Years Ended 2023 2022 2021 Numerator (Dollars in Millions) : Net Earnings $ 3,715 $ 4,166 $ 3,781 Denominator (Units in Millions) : Average Common Shares Outstanding 2,008 2,136 2,250 Other Potentially Dilutive Common Shares 5 5 5 Average Common Shares Outstanding, Assuming Dilution 2,013 2,141 2,255 Net Earnings Per Share, Basic $ 1.85 $ 1.95 $ 1.68 Net Earnings Per Share, Assuming Dilution $ 1.85 $ 1.95 $ 1.68
Schedule of Average Outstanding Equity Awards Excluded from Diluted Earnings Per Share Calculation	The total average outstanding equity awards that were excluded from the diluted earnings per share calculation because their effect was antidilutive is in the table below. Years Ended 2023 2022 2021 Antidilutive Stock Options Excluded from Diluted EPS (Units in Millions) 3 3 2
Schedule of Share Repurchase Activity	During 2023, 2022 and 2021, CSX repurchased the following shares: Years Ended 2023 2022 2021 Shares Repurchased (Units in Millions) 112 151 90 Cost of Shares (Dollars in Millions) $ 3,482 $ 4,731 $ 2,886 Average Price Paid per Share $ 30.95 $ 31.25 $ 31.91

Shareholders' Equity (Tables)

Shareholders' Equity (Tables)	12 Months Ended
Shareholders' Equity (Tables)	Dec. 31, 2023
Stockholders' Equity Note [Abstract]
Schedule of Common and Preferred Stock	Common and preferred stock consists of the following: Common Stock, $1 Par Value December 2023 (Units in Millions) Common Shares Authorized 5,400 Common Shares Issued and Outstanding 1,958 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, 2023
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. Years Ended (Dollars in Millions) 2023 2022 2021 Share-Based Compensation Expense Performance Units $ 20 $ 35 $ 71 Restricted Stock Units and Awards 19 15 12 Stock Options 12 17 18 Employee Stock Purchase Plan 7 5 4 Stock Awards for Directors 2 2 2 Total Share-based Compensation Expense $ 60 $ 74 $ 107 Income Tax Benefit $ 14 $ 17 $ 23
Schedule of Assumptions and Inputs Used to Estimate Fair Value of Performance Units	The fair values of the performance units awarded during the years ended December 2023, 2022 and 2021 were calculated primarily using a Monte-Carlo simulation model with the following weighted-average assumptions: Years Ended Weighted-Average Assumptions Used: 2023 2022 2021 Risk-free Interest Rate 4.4 % 2.3 % 0.2 % Annualized Volatility 33.2 % 33.0 % 33.6 % Expected Life (in years) 2.8 2.7 2.9
Schedule of Performance Unit Grant and Vesting Information	Performance unit grant and vesting information is summarized as follows: Years Ended 2023 2022 2021 Weighted-Average Fair Value of Units Granted $ 31.57 $ 33.89 $ 30.11 Fair Value of Units Vested (in Millions) $ 16 $ 24 $ 19
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, 2022 1,254 $ 32.14 Granted 755 31.57 Forfeited (118) 32.20 Vested (570) 30.23 Unvested at December 31, 2023 1,321 $ 32.65
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: Years Ended 2023 2022 2021 Weighted-Average Fair Value of Units Granted $ 9.82 $ 10.12 $ 7.94 Stock Options Valuation Assumptions: Annual Dividend Yield 1.4 % 1.1 % 1.2 % Risk-free Interest Rate 3.8 % 2.0 % 0.7 % Annualized Volatility 29.6 % 30.1 % 31.2 % Expected Life (in Years) 6.0 6.0 6.0 Other Pricing Model Inputs: Weighted-average Grant-date Market Price of CSX Stock (Strike Price) $ 31.54 $ 35.12 $ 29.65
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, 2022 13,400 $ 24.03 Granted 1,234 31.54 Forfeited (189) 32.68 Exercised (2,351) 22.06 Outstanding at December 31, 2023 12,094 $ 25.04 6.0 $ 117 Exercisable at December 31, 2023 9,239 $ 22.73 5.3 $ 111
Schedule of Intrinsic Value and Cash Proceeds of Options Exercises	Additional information on stock option exercises is summarized as follows: Years Ended (Dollars in Millions) 2023 2022 2021 Intrinsic Value of Stock Options Exercised $ 27 $ 9 $ 32 Cash Received from Option Exercises $ 52 $ 15 $ 31
Schedule of Restricted Stock Grant and Vesting Information	Restricted stock grant and vesting information is summarized as follows: Years Ended 2023 2022 2021 Weighted-Average Fair Value of Units Granted $ 31.46 $ 34.55 $ 29.84 Fair Value of Units and Awards Vested (in Millions) $ 8 $ 5 $ 12
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, 2022 1,552 $ 31.68 Granted 880 31.46 Forfeited (100) 31.92 Vested (303) 27.49 Unvested at December 31, 2023 2,029 $ 31.70
Schedule of Shares Issued under Employee Stock Purchase Plan	During 2023, 2022 and 2021, the Company issued the following shares under this program. Years Ended 2023 2022 2021 Shares Issued (in Thousands) 959 726 730 Weighted Average Purchase Price Per Share $ 25.66 $ 25.93 $ 21.90

Casualty, Environmental and O_2

Casualty, Environmental and Other Reserves (Tables)	12 Months Ended
Casualty, Environmental and Other Reserves (Tables)	Dec. 31, 2023
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 31, 2020 $ 196 $ 76 $ 42 $ 314 Assumed in Acquisition of Quality Carriers — 29 33 62 Charged to Expense 55 26 49 130 Payments (71) (23) (44) (138) December 31, 2021 180 108 80 368 Assumed in Acquisition of Pan Am 19 36 — 55 Charged to Expense 45 47 51 143 Payments (50) (30) (50) (130) December 31, 2022 194 161 81 436 Charged to Expense 69 29 67 165 Payments (68) (36) (57) (161) December 31, 2023 $ 195 $ 154 $ 91 $ 440
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 2023 December 2022 (Dollars in Millions) Current Long-term Total Current Long-term Total Casualty: Personal Injury $ 45 $ 83 $ 128 $ 40 $ 86 $ 126 Occupational 7 60 67 10 58 68 Total Casualty $ 52 $ 143 $ 195 $ 50 $ 144 $ 194 Environmental 41 113 154 53 108 161 Other 51 40 91 41 40 81 Total $ 144 $ 296 $ 440 $ 144 $ 292 $ 436

Properties (Tables)

Properties (Tables)	12 Months Ended
Properties (Tables)	Dec. 31, 2023
Property, Plant and Equipment [Abstract]
Schedule of Net Properties	Details of the Company’s net properties are as follows: (Dollars in Millions) Accumulated Net Book Annual Depreciation Estimated Useful Life Depreciation December 2023 Cost Depreciation Value Rate (Avg. Years) Method Road Rail and Other Track Material $ 9,537 $ (1,978) $ 7,559 2.5% 41 Group Life Ties 7,020 (2,131) 4,889 3.5% 28 Group Life Grading 2,796 (668) 2,128 1.3% 75 Group Life Ballast 3,424 (1,119) 2,305 2.6% 38 Group Life Bridges, Trestles, and Culverts 3,121 (525) 2,596 1.7% 60 Group Life Signals and Interlockers 3,376 (1,351) 2,025 4.1% 24 Group Life Buildings 1,530 (608) 922 2.5% 40 Group Life/ Straight Line (a) Other 5,786 (2,546) 3,240 4.1% 25 Group Life/ Straight Line (a) Total Road 36,590 (10,926) 25,664 Equipment Locomotive 4,952 (1,981) 2,971 3.8% 26 Group Life Freight Cars 2,300 (378) 1,922 3.1% 32 Group Life Work Equipment and Other 3,391 (2,100) 1,291 8.9% 11 Group Life/ Straight Line (a) Total Equipment 10,643 (4,459) 6,184 Land 2,272 — 2,272 N/A N/A N/A Construction In Progress 815 — 815 N/A N/A N/A Total Properties $ 50,320 $ (15,385) $ 34,935 (a) For depreciation method, certain asset categories contain intermodal terminals, trucking 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 2022 Cost Depreciation Value Rate (Avg. Years) Method Road Rail and Other Track Material $ 8,660 $ (1,405) $ 7,255 2.5% 41 Group Life Ties 6,763 (2,010) 4,753 3.5% 28 Group Life Grading 2,741 (637) 2,104 1.3% 75 Group Life Ballast 3,383 (1,130) 2,253 2.6% 38 Group Life Bridges, Trestles, and Culverts 2,989 (454) 2,535 1.7% 60 Group Life Signals and Interlockers 3,299 (1,210) 2,089 4.1% 24 Group Life Buildings 1,416 (558) 858 2.5% 40 Group Life/ Straight Line (a) Other 5,541 (2,323) 3,218 4.1% 25 Group Life/ Straight Line (a) Total Road 34,792 (9,727) 25,065 Equipment Locomotive 4,848 (1,856) 2,992 3.8% 26 Group Life Freight Cars 2,316 (369) 1,947 3.1% 32 Group Life Work Equipment and Other 3,132 (1,911) 1,221 8.9% 11 Group Life/ Straight Line (a) Total Equipment 10,296 (4,136) 6,160 Land 2,272 — 2,272 N/A N/A N/A Construction In Progress 745 — 745 N/A N/A N/A Total Properties $ 48,105 $ (13,863) $ 34,242
Disclosure of Long-Lived Assets Held-for-sale	Years Ended (Dollars in Millions) 2023 2022 2021 Gains $ — $ 144 $ 349 Proceeds — 125 400

Leases (Tables)

Leases (Tables)	12 Months Ended
Leases (Tables)	Dec. 31, 2023
Leases [Abstract]
Schedule of Amount, Timing and Uncertainty of Cash Flows of Company's Operating Leases	The following table presents information about the amount, timing and uncertainty of cash flows arising from all of the Company’s operating leases as of December 31, 2023 . (Dollars in Millions) December 2023 Maturity of Lease Liabilities Lease Payments 2024 $ 70 2025 67 2026 51 2027 43 2028 35 Thereafter 1,108 Total Undiscounted Operating Lease Payments $ 1,374 Less: Imputed Interest (815) Present Value of Operating Lease Liabilities $ 559 (Dollars in Millions) Conrail Shared Years Asset Agreement 2024 $ 32 2025 32 2026 32 2027 32 2028 32 Thereafter 13 Total $ 173
Schedule of Balance Sheet Classification and Other Information of Company's Operating Leases	(Dollars in Millions) 2023 2022 Balance Sheet Classification Right of Use Asset $ 498 $ 505 Current Lease Liabilities (Included in Other Current Liabilities) $ 68 $ 69 Long-term Lease Liabilities 491 488 Total Operating Lease Liabilities $ 559 $ 557 Other Information Weighted-average Remaining Lease Term for Operating Leases 30 years 31 years Weighted-average Discount Rate for Operating Leases 5.1 % 5.0 %
Schedule of Operating Lease Costs	These amounts are shown in the table below. Years Ended (Dollars in Millions) 2023 2022 2021 Rent Expense on Operating Leases $ 109 $ 109 $ 89

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
Commitments and Contingencies (Tables)	Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Schedule of Number of Locomotives and Payments under Long-term Maintenance Program	The following table summarizes CSXT’s payments, including prepayments, for the long-term maintenance program which covers approximately 1,900 locomotives with payments based on active status during the period. Years Ended (a) (Dollars in Millions) 2023 2022 2021 Amounts Paid $ 200 $ 168 $ 99 (a) The 2022 amount has been updated to include prepayments of $40 million.
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 Total 2024 $ 342 $ 182 $ 524 2025 365 137 502 2026 397 37 434 2027 521 37 558 2028 402 33 435 Thereafter 1,223 56 1,279 Total $ 3,250 $ 482 $ 3,732

Employee Benefit Plans (Tables)

Employee Benefit Plans (Tables)	12 Months Ended
Employee Benefit Plans (Tables)	Dec. 31, 2023
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 . As of Pension Plan Participants: January 1, 2023 Active Employees 2,479 Retirees and Beneficiaries 11,294 Other (a) 3,504 Total 17,277 (a) The Other category consists mostly of terminated but vested former employees.
Schedule of Future Expected Benefit Payments	Future expected benefit payments are as follows: Expected Cash Flows (Dollars in Millions): Pension Benefits 2024 $ 190 2025 186 2026 183 2027 182 2028 181 2029-2033 870 Total $ 1,792
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 2023 December 2022 Percent of Percent of (Dollars in Millions) Amount Total Assets Amount Total Assets Equity $ 1,142 47 % $ 1,249 54 % Fixed Income 114 4 144 6 Cash and Cash Equivalents 15 1 41 2 Growth-Oriented $ 1,271 52 % $ 1,434 62 % Fixed Income 911 38 777 33 Cash and Cash Equivalents 240 10 116 5 Immunizing $ 1,151 48 % $ 893 38 % Total $ 2,422 100 % $ 2,327 100 %
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 2023 and 2022 plan years are as follows: Pension Benefits Plan Year Plan Year (Dollars in Millions) 2023 2022 Actuarial Present Value of Benefit Obligation Accumulated Benefit Obligation $ 2,252 $ 2,285 Projected Benefit Obligation 2,343 2,368 Change in Projected Benefit Obligation: Projected Benefit Obligation at Beginning of Plan Year $ 2,368 $ 3,022 Service Cost (a) 28 36 Interest Cost 111 64 Actuarial Loss (Gain) 20 (570) Benefits Paid (184) (184) Benefit Obligation at End of Plan Year $ 2,343 $ 2,368 Change in Plan Assets: Fair Value of Plan Assets at Beginning of Plan Year $ 2,327 $ 3,016 Actual Return (Loss) on Plan Assets 259 (523) Non-qualified Employer Contributions 20 18 Benefits Paid (184) (184) Fair Value of Plan Assets at End of Plan Year $ 2,422 $ 2,327 Funded Status at End of Plan Year $ 79 $ (41) (a) Service cost for 2023 and 2022 includes capitalized service costs of $4 million each year.
Schedule of Amount Recognized in Balance Sheet	Amounts related to pension 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 December December (Dollars in Millions) 2023 2022 Amounts Recorded in Consolidated Balance Sheets: Long-term Assets $ 277 $ 164 Current Liabilities (16) (17) Long-term Liabilities (182) (188) Net Amount Recognized in Consolidated Balance Sheets $ 79 $ (41)
Schedule of Benefit Obligations in Excess of Plan Assets	The following table shows the value of plan assets for only those plans with a net liability status. Aggregate (Dollars in Millions) Fair Value Aggregate Benefit Obligations in Excess of Plan Assets of Plan Assets Benefit Obligation Projected Benefit Obligation $ — $ (198) Accumulated Benefit Obligation — (188)
Schedule of Net Benefit Expense Recorded on the Income Statement	The following table describes the components of expense/(income) related to net benefit expense recorded on the income statement. Pension Benefits (Dollars in Millions) 2023 2022 2021 Service Cost Included in Labor and Fringe $ 24 $ 32 $ 41 Interest Cost 111 64 55 Expected Return on Plan Assets (164) (188) (186) Amortization of Net Loss 29 50 73 Total Income Included in Other Income - Net $ (24) $ (74) $ (58) Net Periodic Benefit Cost (Credit) $ — $ (42) $ (17) Settlement Loss — 1 — Total Periodic Benefit Cost (Credit) $ — $ (41) $ (17)
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 benefits. (Dollars in Millions) Pension Benefits Components of Other Comprehensive Years Ended Loss (Income) 2023 2022 Recognized in the Balance Sheet (Gains) Losses $ (75) $ 141 Expense Recognized in the Income Statement Amortization of Net Losses $ 29 $ 50 Settlement Loss — 1
Schedule of Weighted-Average Assumptions Used	The weighted averages of assumptions used by the Company to value its pension obligations were as follows: Pension Benefits 2023 2022 Expected Long-term Return on Plan Assets: Benefit Cost for Current Plan Year 6.75 % 6.75 % Benefit Cost for Subsequent Plan Year 6.75 % 6.75 % Discount Rates: Benefit Cost for Plan Year Service Cost for Plan Year 5.09 % 2.98 % Interest Cost for Plan Year 4.90 % 2.18 % Benefit Obligation at End of Plan Year 4.82 % 5.02 % Salary Scale Inflation 4.80 % 4.80 % Cash Balance Plan Interest Credit Rate 3.75 % 3.75 %

Debt and Credit Agreements (Tab

Debt and Credit Agreements (Tables)	12 Months Ended
Debt and Credit Agreements (Tables)	Dec. 31, 2023
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments	Debt at December 2023 and December 2022 is shown in the table below. For information regarding the fair value of debt, see Note 13, Fair Value Measurements . Maturity at Average December December (Dollars in Millions) 2023 2023 2023 2022 Notes 2024-2068 4.2% $ 18,514 $ 17,877 Equipment Obligations (a) 2024-2027 4.4% 2 141 Finance Leases 2024-2032 5.9% 17 29 Subtotal Long-term Debt (Including Current Portion) $ 18,533 $ 18,047 Less Debt Due within One Year (558) (151) Long-term Debt (Excluding Current Portion) $ 17,975 $ 17,896 (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 Years Ending December 2023 2024 $ 558 2025 606 2026 704 2027 998 2028 1,001 Thereafter 14,666 Total Long-term Debt Maturities, including current portion $ 18,533
Schedule of Interest Rate Derivatives	The cumulative adjustment to the hedged notes is included in long-term debt on the consolidated balance sheet as shown in the following table. (Dollars in Millions) December 31, 2023 December 31, 2022 Notional Value of Hedged Notes $ 1,050 $ 800 Fair Value Asset Adjustment to Hedged Notes 19 — Fair Value Liability Adjustment to Hedged Notes (107) (118) Carrying Amount of Hedged Notes $ 962 $ 682 (Dollars in Millions) 2023 2022 2021 Interest Expense Impact (Increase) Decrease $ (28) $ (1) N/A
Derivative Instruments, Gain (Loss)	Unrealized amounts related to the hedge, recorded net of tax in other comprehensive income, are summarized in the table below. (Dollars in Millions) 2023 2022 2021 Unrealized Gain - Net $ — $ 80 $ 8

Revenues (Tables)

Revenues (Tables)	12 Months Ended
Revenues (Tables)	Dec. 31, 2023
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. Years Ended (Dollars in Millions) 2023 2022 2021 Chemicals $ 2,599 $ 2,584 $ 2,421 Agricultural and Food Products 1,657 1,664 1,461 Automotive 1,219 1,054 886 Forest Products 1,012 996 918 Metals and Equipment 917 828 796 Minerals 733 658 587 Fertilizers 516 455 470 Total Merchandise 8,653 8,239 7,539 Coal 2,484 2,434 1,790 Intermodal 2,060 2,306 2,039 Trucking (a) 882 966 410 Other 578 908 744 Total $ 14,657 $ 14,853 $ 12,522 (a) Effective third quarter 2021, Trucking revenue is comprised of revenue from the operations of Quality Carriers, which was acquired by CSX effective July 1, 2021.
Schedule of Accounts Receivable, Net	The Company’s accounts receivable - net consists of freight and non-freight receivables, reduced by an allowance for credit losses. (Dollars in Millions) December 31, December 31, Freight Receivables $ 1,047 $ 1,067 Freight Allowance for Credit Losses (18) (16) Freight Receivables, net 1,029 1,051 Non-Freight Receivables 378 279 Non-Freight Allowance for Credit Losses (14) (17) Non-Freight Receivables, net 364 262 Total Accounts Receivable, net $ 1,393 $ 1,313

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
Income Taxes (Tables)	Dec. 31, 2023
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: Years Ended (Dollars in Millions) 2023 2022 2021 Current: Federal $ 852 $ 928 $ 827 State 184 203 176 Subtotal Current $ 1,036 $ 1,131 $ 1,003 Deferred: Federal 122 166 166 State 18 (49) 1 Subtotal Deferred $ 140 $ 117 $ 167 Total Income Tax Expense $ 1,176 $ 1,248 $ 1,170
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. Years Ended (Dollars in Millions) 2023 2022 2021 Federal Income Taxes $ 1,027 21.0 % $ 1,137 21.0 % $ 1,040 21.0 % State Income Taxes 153 3.1 % 121 2.2 % 139 2.8 % Other (4) (0.1) % (10) (0.1) % (9) (0.2) % Income Tax Expense/ Rate $ 1,176 24.0 % $ 1,248 23.1 % $ 1,170 23.6 %
Schedule of Significant Components of Deferred Income Tax Assets and Liabilities	The significant components of deferred income tax assets and liabilities include: 2023 2022 (Dollars in Millions) Assets Liabilities Assets Liabilities Other Employee Benefit Plans $ 103 $ — $ 105 $ — Accelerated Depreciation — 7,678 — 7,600 Other 459 630 553 627 Total $ 562 $ 8,308 $ 658 $ 8,227 Net Deferred Income Tax Liabilities $ 7,746 $ 7,569

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
Fair Value Measurements (Tables)	Dec. 31, 2023
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. December 2023 December 2022 (Dollars in Millions) Level 1 Level 2 Total Level 1 Level 2 Total Fixed Income Mutual Funds $ 80 $ — $ 80 $ 89 $ — $ 89 Corporate Bonds — 60 60 — 49 49 Government Securities — 41 41 — 58 58 Total Investments at Fair Value $ 80 $ 101 $ 181 $ 89 $ 107 $ 196 Total Investments at Amortized Cost $ 184 $ 201
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 2023 December 2022 Less than 1 year $ 83 $ 129 1 - 5 years 37 24 5 - 10 years 17 10 Greater than 10 years 44 33 Total investments at fair value $ 181 $ 196
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 2023 December 2022 Long-term Debt (Including Current Maturities): Fair Value $ 17,528 $ 16,135 Carrying Value 18,533 18,047
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 2023 and 2022 are shown in the table below. For additional information related to pension assets, see Note 9, Employee Benefit Plans . December 2023 December 2022 (Dollars in Millions) Level 1 Level 2 Total Level 1 Level 2 Total Common Stock $ 340 $ — $ 340 $ 335 $ — $ 335 Mutual Funds 32 — 32 29 — 29 Cash and Cash Equivalents 255 — 255 157 — 157 Corporate Bonds — 646 646 — 647 647 Government Securities — 126 126 — 88 88 Asset-backed Securities, Derivatives and Other — 10 10 — 9 9 Total Investments in the Fair Value Hierarchy $ 627 $ 782 $ 1,409 $ 521 $ 744 $ 1,265 Investments Measured at Net Asset Value (a) n/a n/a $ 1,013 n/a n/a $ 1,062 Investments at Fair Value $ 627 $ 782 $ 2,422 $ 521 $ 744 $ 2,327

Other Income - Net (Tables)

Other Income - Net (Tables)	12 Months Ended
Other Income - Net (Tables)	Dec. 31, 2023
Other Income and Expenses [Abstract]
Schedule of Other Income - Net	Other income – net consisted of the following: Years Ended (Dollars in Millions) 2023 2022 2021 Net Periodic Pension and Post-retirement Benefit Credit (a) $ 29 $ 79 $ 64 Interest Income 79 42 7 Miscellaneous Income 31 12 8 Total Other Income - Net $ 139 $ 133 $ 79

Investment in Affiliates and _2

Investment in Affiliates and Related-Party Transactions (Tables)	12 Months Ended
	Dec. 31, 2023
Related Party Transactions [Abstract]
Schedule of Equity-method Investments in Affiliates	CSX's investments in affiliates are included on the consolidated balance sheet as investments in affiliates and other companies. December December (Dollars in Millions) 2023 2022 Conrail $ 1,175 $ 1,124 TTX 961 914 Other Equity Method and Cost Method Investments 261 254 Total $ 2,397 $ 2,292
Schedule of Future Payments Under Shared Asset Area Agreements	The following table presents information about the amount, timing and uncertainty of cash flows arising from all of the Company’s operating leases as of December 31, 2023 . (Dollars in Millions) December 2023 Maturity of Lease Liabilities Lease Payments 2024 $ 70 2025 67 2026 51 2027 43 2028 35 Thereafter 1,108 Total Undiscounted Operating Lease Payments $ 1,374 Less: Imputed Interest (815) Present Value of Operating Lease Liabilities $ 559 (Dollars in Millions) Conrail Shared Years Asset Agreement 2024 $ 32 2025 32 2026 32 2027 32 2028 32 Thereafter 13 Total $ 173
Schedule of Related Party Transactions	The following table discloses amounts related to Conrail. All amounts in the table below are included in purchased services and other expenses on the Company’s consolidated income statements. Years Ended (Dollars in Millions) 2023 2022 2021 Rents, Fees and Services $ 132 $ 130 $ 128 Purchase Price Amortization and Other 4 4 4 Equity Earnings of Conrail (54) (44) (44) Total Conrail Expense $ 82 $ 90 $ 88 December December (Dollars in Millions) 2023 2022 Balance Sheet Information: CSX Accounts Payable to Conrail $ 154 $ 136 Promissory Notes Payable to Conrail Subsidiary 1.31% CSX Promissory Note due December 2050 73 73 1.31% CSXT Promissory Note due December 2050 368 368 As required by the Related Party Disclosures Topic in the ASC, the following table discloses amounts related to TTX. Car hire rents and equity earnings are included in equipment and other rents expense on the Company’s consolidated income statement. Years Ended (Dollars in Millions) 2023 2022 2021 Income Statement Information: Car Hire Rents $ 249 $ 241 $ 221 Equity Earnings of TTX (49) (51) (52) Total TTX Expense $ 200 $ 190 $ 169 Also included below is balance sheet information related to CSX's payable to TTX, which represents car rental liabilities. (Dollars in Millions) December December Balance Sheet Information: 2023 2022 CSX Payable to TTX $ 43 $ 38

Other Comprehensive Income (L_2

Other Comprehensive Income (Loss) (Tables)	12 Months Ended
Other Comprehensive Income (Loss) (Tables)	Dec. 31, 2023
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. Interest rate derivatives consist of forward starting interest rate swaps classified as cash flow hedges. See Note 10, Debt and Credit Agreements, for further information. Items classified as other primarily represent CSX's share of AOCI of equity method investees. Amounts reclassified in other to net earnings are included in purchased services and other or equipment and other rents on the consolidated income statements. Pension and Other Post-Employment Benefits Interest Rate Derivatives Other Accumulated Other Comprehensive (Loss) Income (Dollars in Millions) Balance December 31, 2020 - Net of Tax $ (598) $ 62 $ (62) $ (598) Other Comprehensive Income (Loss) Income Before Reclassifications 147 11 — 158 Amounts Reclassified to Net Earnings 66 — 15 81 Tax Expense (46) (3) — (49) Total Other Comprehensive Income $ 167 $ 8 $ 15 $ 190 Balance December 31, 2021 - Net of Tax $ (431) $ 70 $ (47) $ (408) Other Comprehensive Income (Loss) (Loss) Income Before Reclassifications (129) 88 — (41) Amounts Reclassified to Net Earnings 44 — 2 46 Tax Benefit (Expense) 19 (8) 4 15 Total Other Comprehensive (Loss) Income $ (66) $ 80 $ 6 $ 20 Balance December 31, 2022 - Net of Tax $ (497) $ 150 $ (41) $ (388) Other Comprehensive Income (Loss) Income Before Reclassifications 75 16 — 91 Amounts Reclassified to Net Earnings 18 — 5 23 Tax Expense (19) (16) (3) (38) Total Other Comprehensive Income $ 74 $ — $ 2 $ 76 Balance December 31, 2023 - Net of Tax $ (423) $ 150 $ (39) $ (312)

Business Combinations (Tables)

Business Combinations (Tables)	12 Months Ended
Business Combinations (Tables)	Dec. 31, 2023
Business Combination and Asset Acquisition [Abstract]
Schedule of Allocation of Total Consideration to Fair Value of Assets and Liabilities of Quality Carriers	The allocation of total consideration to the fair values of the acquired assets and liabilities of Pan Am is summarized in the table below. (Dollars in Millions) June 1, 2022 Assets Acquired: Accounts Receivable, net $ 46 Properties and Equipment, net 600 Goodwill 17 Investments in Affiliates 90 Other Assets 11 Total Assets Acquired $ 764 Liabilities Assumed: Accounts Payable and Accrued Liabilities $ 32 Deferred Tax Liabilities 75 Other Long-term Liabilities 57 Total Liabilities Assumed $ 164 Fair Value of Assets Acquired, Net of Liabilities Assumed: $ 600 (Dollars in Millions) July 1, 2021 Assets Acquired: Cash and Cash Equivalents $ 3 Accounts Receivable, net 113 Properties and Equipment, net 225 Goodwill 213 Intangible Assets 180 Other Assets 9 Total Assets Acquired $ 743 Liabilities Assumed: Accounts Payable and Accrued Liabilities $ 48 Finance Lease Obligations and Notes Payable 68 Casualty, Environmental and Other Reserves 62 Other Long-term Liabilities 21 Total Liabilities Assumed $ 199 Fair Value of Assets Acquired, Net of Liabilities Assumed: $ 544

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	12 Months Ended
Goodwill and Other Intangible Assets (Tables)	Dec. 31, 2023
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill and Other Intangible Asset Balances	The following table presents goodwill and other intangible asset balances and adjustments to those balances for the years ended December 31, 2023 and 2022: Goodwill Intangible Assets (Dollars in Millions) Net Carrying Amount Cost Accumulated Amortization Net Carrying Amount Total Goodwill and Other Intangible Assets - Net Balance at December 31, 2021 $ 276 $ 180 $ (5) $ 175 $ 451 Additions 43 18 — 18 61 Amortization — — (10) (10) (10) Balance at December, 31, 2022 $ 319 $ 198 $ (15) $ 183 $ 502 Additions 6 8 — 8 14 Amortization — — (10) (10) (10) Balance at December, 31, 2023 $ 325 $ 206 $ (25) $ 181 $ 506

Nature of Operations and Sign_3

Nature of Operations and Significant Accounting Policies - Narrative (Details) carload in Thousands, $ in Millions			12 Months Ended
	Jun. 18, 2021 shares	Jun. 04, 2021	Dec. 31, 2023 USD ($) employee carload line_of_business state site terminal operatingSegment port_terminal railroad mi	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Revenue from External Customer [Line Items]
Number of rail route miles \| mi			20,000
Rail network states number \| state			26
Number of ocean, river and lake ports serviced (over) \| port_terminal			70
Number of short-line and regional railroads served (more than) \| railroad			240
Revenue			$ 14,657	$ 14,853	$ 12,522
Number of primary lines of business \| line_of_business			4
Number of operating segments \| operatingSegment			2
Number of reportable segments \| site			1
Number of employees (more than) \| employee			23,000
Number of union employees \| employee			17,700
Stock split conversion ratio		3
Number of additional shares of common stock received for each share held after stock split (in shares) \| shares	2
Cost method, maximum percentage			20%
Merchandise business
Revenue from External Customer [Line Items]
Revenue			$ 8,653	8,239	7,539
Number of carloads \| carload			2,600
Percentage of total volume			43%
Percentage of total revenue			59%
Intermodal business
Revenue from External Customer [Line Items]
Revenue			$ 2,060	2,306	2,039
Number of carloads \| carload			755
Percentage of total volume			45%
Percentage of total revenue			14%
Number of terminals \| terminal			30
Coal business
Revenue from External Customer [Line Items]
Revenue			$ 2,484	2,434	1,790
Number of carloads \| carload			2,800
Percentage of total volume			12%
Percentage of total revenue			17%
Trucking business
Revenue from External Customer [Line Items]
Revenue			$ 882	966	410
Percentage of total revenue			6%
Other
Revenue from External Customer [Line Items]
Revenue			$ 578	$ 908	$ 744
Percentage of total revenue			4%

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	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Numerator:
Net Earnings	$ 3,715	$ 4,166	$ 3,781
Denominator:
Average Common Shares Outstanding (in shares)	2,008	2,136	2,250
Other Potentially Dilutive Common Shares (in shares)	5	5	5
Average Common Shares Outstanding, Assuming Dilution (in shares)	2,013	2,141	2,255
Net Earnings Per Share, Basic (in dollars per share)	$ 1.85	$ 1.95	$ 1.68
Net Earnings Per Share, Assuming Dilution (in dollars per share)	$ 1.85	$ 1.95	$ 1.68

Earnings Per Share - Antidiluti

Earnings Per Share - Antidilutive Stock Options Excluded from Diluted Earnings Per Share Calculation (Details) - shares shares in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	3	3	2

Earnings Per Share - Narrative

Earnings Per Share - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Oct. 17, 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of shares repurchased (in shares)	112,000,000	151,000,000	90,000,000
Amount of shares repurchased	$ 3,482	$ 4,731	$ 2,886
Common stock dividends, per share (in dollars per share)	$ 0.44	$ 0.40	$ 0.37
Share Repurchase Program October 2023
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Share repurchase program authorized amount				$ 5,000
Share repurchase program, remaining amount	$ 4,800
Structured Share Repurchase Program
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of shares repurchased (in shares)			12,000,000
Amount of shares repurchased			$ 378
Share repurchase agreement outstanding	0	0

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, 2023	Dec. 31, 2022	Dec. 31, 2021
Earnings Per Share [Abstract]
Stock repurchased (in shares)	112	151	90
Cost of shares	$ 3,482	$ 4,731	$ 2,886
Average price paid per share (in dollars per share)	$ 30.95	$ 31.25	$ 31.91

Shareholders' Equity - Common a

Shareholders' Equity - Common and Preferred Stock (Details) - $ / shares shares in Millions	Dec. 31, 2023	Dec. 31, 2022
Stockholders' Equity Note [Abstract]
Common stock par value (in dollars per share)	$ 1	$ 1
Common shares authorized (in shares)	5,400
Common shares issued (in shares)	1,958
Common shares outstanding (in shares)	1,958
Preferred shares authorized (in shares)	25
Preferred shares issued (in shares)	0
Preferred shares outstanding (in shares)	0

Shareholders' Equity - Narrativ

Shareholders' Equity - Narrative (Details)			12 Months Ended
Shareholders' Equity - Narrative (Details)	Jun. 18, 2021 shares	Jun. 04, 2021	Dec. 31, 2023 USD ($) $ / shares	Dec. 31, 2022 USD ($)	Jun. 30, 2021 USD ($)
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Common stock, number of votes per share \| $ / shares			$ 1
Stock split conversion ratio		3
Number of additional shares of common stock received for each share held after stock split (in shares) \| shares	2
Reclassification to other capital			$ (9,790,000,000)	$ (10,363,000,000)
Reclassification from retained earnings			$ 691,000,000	$ 574,000,000	$ 0
Revision of Prior Period, Reclassification, Adjustment \| Stock split reclassification adjustment
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Reclassification to other capital					1,000,000,000
Reclassification from retained earnings					$ 1,000,000,000

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, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	$ 60	$ 74	$ 107
Income Tax Benefit	14	17	23
Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	20	35	71
Restricted Stock Units and Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	19	15	12
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	12	17	18
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	7	5	4
Stock Awards for Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total Share-based Compensation Expense	$ 2	$ 2	$ 2

Stock Plans and Share-Based C_4

Stock Plans and Share-Based Compensation - Narrative (Details)	8 Months Ended	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2023 USD ($) plan shares	Dec. 31, 2022 plan	Dec. 31, 2021 plan	May 31, 2018 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period prior to grant date		3 years
Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost		$ 20,000,000
Look-back period		2 years 9 months 18 days	2 years 8 months 12 days	2 years 10 months 24 days
Expected weighted average period of recognition for unrecognized compensation cost (in years)		2 years
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost		$ 28,000,000
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
Restricted Stock \| Share-Based Payment Arrangement, Cliff Vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award performance period		3 years
Restricted Stock \| Share-Based Payment Arrangement, Graduated Vesting
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award performance period		3 years
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost		$ 12,000,000
Look-back period		6 years	6 years	6 years
Expected weighted average period of recognition for unrecognized compensation cost (in years)		2 years
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		$ 130,000
Annual retainer to be paid to non-management directors, common stock option		180,000
Chairman
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual grant of common stock amount		$ 250,000
LITP \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout range (as a percent)		0%
LITP \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payout range (as a percent)		200%
LITP \| Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equivalent shares of CSX common stock per unit of award (in shares) \| shares		1
Award performance period		3 years
Number of long term incentive plans \| plan		3	3	3
LITP \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equivalent shares of CSX common stock per unit of award (in shares) \| shares		1
LITP \| Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equivalent shares of CSX common stock per unit of award (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 \| Certain Executive Officers \| Performance Units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of payout subject to adjustment		25%
LITP \| Certain Executive Officers \| Performance Units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of payout subject to adjustment		250%
2021-2023 LTIP \| Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award performance period		3 years	3 years	3 years
Percentage payout on operating ratio		50%
2020-2022 LTIP \| Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award performance period		3 years	3 years	3 years
2019-2021 LTIP \| Performance Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award performance period		3 years	3 years	3 years
ESPP \| Employee Stock Purchase Plan
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					12,000,000
Employee contribution percentage, minimum					1%
Employee contribution percentage, maximum					10%
Maximum value of stocks purchased by employee, after tax					$ 25,000
Percentage of share closing market price	85%
Share offering period	6 months

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, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free Interest Rate	4.40%	2.30%	0.20%
Annualized Volatility	33.20%	33%	33.60%
Expected Life (in years)	2 years 9 months 18 days	2 years 8 months 12 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, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value (in dollars per share)	$ 31.57	$ 33.89	$ 30.11
Fair Value of Units Vested (in Millions)	$ 16	$ 24	$ 19

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, 2023 $ / shares shares
Weighted-Average Fair Value at Grant Date
Unvested at December 31, 2022 (in dollars per share)	$ 33.89
Unvested at December 31, 2023 (in dollars per share)	$ 31.57
Long-term Incentive Plans
Units Outstanding
Unvested at December 31, 2022 (in shares) \| shares	1,254
Granted (in shares) \| shares	755
Forfeited (in shares) \| shares	(118)
Vested (in shares) \| shares	(570)
Unvested at December 31, 2023 (in shares) \| shares	1,321
Weighted-Average Fair Value at Grant Date
Unvested at December 31, 2022 (in dollars per share)	$ 32.14
Granted (in dollars per share)	31.57
Forfeited (in dollars per share)	32.20
Vested (in dollars per share)	30.23
Unvested at December 31, 2023 (in dollars per share)	$ 32.65

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, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value (in dollars per share)	$ 9.82	$ 10.12	$ 7.94
Annual dividend yield	1.40%	1.10%	1.20%
Risk-free Interest Rate	3.80%	2%	0.70%
Annualized Volatility	29.60%	30.10%	31.20%
Expected Life (in years)	6 years	6 years	6 years
Weighted-average grant-date market price of CSX stock (strike price) (in dollars per share)	$ 31.54	$ 35.12	$ 29.65

Stock Plans and Share-Based C_9

Stock Plans and Share-Based Compensation - Stock Option Activity (Details) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($) $ / shares shares
Stock Options Outstanding
Outstanding at December 31, 2022 (in shares) \| shares	13,400
Granted (in shares) \| shares	1,234
Forfeited (in shares) \| shares	(189)
Exercised (in shares) \| shares	(2,351)
Outstanding at December 31, 2023 (in shares) \| shares	12,094
Weighted-Average Exercise Price
Outstanding at December 31, 2022 (in dollars per share) \| $ / shares	$ 24.03
Granted (in dollars per share) \| $ / shares	31.54
Forfeited (in dollars per share) \| $ / shares	32.68
Exercised (in dollars per share) \| $ / shares	22.06
Outstanding at December 31, 2023 (in dollars per share) \| $ / shares	$ 25.04
Outstanding at December 31, 2023, Weighted-average Remaining Contractual Life (in Years)	6 years
Outstanding at December 31, 2023, Aggregate Intrinsic Value \| $	$ 117
Exercisable at December 31, 2023 (in shares) \| shares	9,239
Exercisable at December 31, 2023, Weighted-Average Exercise Price (in dollars per share) \| $ / shares	$ 22.73
Exercisable at December 31, 2023, Weighted-Average Remaining Contractual Life (in Years)	5 years 3 months 18 days
Exercisable at December 31, 2023, Aggregate Intrinsic Value \| $	$ 111

Stock Plans and Share-Based _10

Stock Plans and Share-Based Compensation - Intrinsic Value and Cash Received on Exercises (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-Based Payment Arrangement [Abstract]
Intrinsic Value of Stock Options Exercised	$ 27	$ 9	$ 32
Cash Received from Option Exercises	$ 52	$ 15	$ 31

Stock Plans and Share-Based _11

Stock Plans and Share-Based Compensation - Restricted Stock Grant and Vesting Information (Details) - Stock Options - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted-average grant date fair value (in dollars per share)	$ 31.46	$ 34.55	$ 29.84
Fair Value of Units Vested (in Millions)	$ 8	$ 5	$ 12

Stock Plans and Share-Based _12

Stock Plans and Share-Based Compensation - Outstanding Restricted Stock Units and Award (Details) - Stock Options shares in Thousands	12 Months Ended
	Dec. 31, 2023 $ / shares shares
Units Outstanding
Unvested at December 31, 2022 (in shares) \| shares	1,552
Granted (in shares) \| shares	880
Forfeited (in shares) \| shares	(100)
Vested (in shares) \| shares	(303)
Unvested at December 31, 2023 (in shares) \| shares	2,029
Weighted-Average Fair Value at Grant Date
Unvested at December 31, 2022 (in dollars per share) \| $ / shares	$ 31.68
Granted (in dollars per share) \| $ / shares	31.46
Forfeited (in dollars per share) \| $ / shares	31.92
Vested (in dollars per share) \| $ / shares	27.49
Unvested at December 31, 2023 (in dollars per share) \| $ / shares	$ 31.70

Stock Plans and Share-Based _13

Stock Plans and Share-Based Compensation - Shares Issued Under Employee Stock Purchase Plan (Details) - ESPP - Employee Stock Purchase Plan - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued (in shares)	959	726	730
Weighted average purchase price per share (in dollars per share)	$ 25.66	$ 25.93	$ 21.90

Casualty, Environmental and O_3

Casualty, Environmental and Other Reserves - Schedule of Claims Activity (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Loss Contingency Accrual [Roll Forward]
Balance at beginning of period	$ 436	$ 368	$ 314
Charged to Expense	165	143	130
Payments	(161)	(130)	(138)
Balance end of period	440	436	368
Quality Carriers, Inc.
Loss Contingency Accrual [Roll Forward]
Assumed in Acquisition			62
Pan-Am
Loss Contingency Accrual [Roll Forward]
Assumed in Acquisition		55
Casualty Reserves
Loss Contingency Accrual [Roll Forward]
Balance at beginning of period	194	180	196
Charged to Expense	69	45	55
Payments	(68)	(50)	(71)
Balance end of period	195	194	180
Casualty Reserves \| Quality Carriers, Inc.
Loss Contingency Accrual [Roll Forward]
Assumed in Acquisition			0
Casualty Reserves \| Pan-Am
Loss Contingency Accrual [Roll Forward]
Assumed in Acquisition		19
Environmental Reserves
Loss Contingency Accrual [Roll Forward]
Balance at beginning of period	161	108	76
Charged to Expense	29	47	26
Payments	(36)	(30)	(23)
Balance end of period	154	161	108
Environmental Reserves \| Quality Carriers, Inc.
Loss Contingency Accrual [Roll Forward]
Assumed in Acquisition			29
Environmental Reserves \| Pan-Am
Loss Contingency Accrual [Roll Forward]
Assumed in Acquisition		36
Other Reserves
Loss Contingency Accrual [Roll Forward]
Balance at beginning of period	81	80	42
Charged to Expense	67	51	49
Payments	(57)	(50)	(44)
Balance end of period	$ 91	81	80
Other Reserves \| Quality Carriers, Inc.
Loss Contingency Accrual [Roll Forward]
Assumed in Acquisition			$ 33
Other Reserves \| Pan-Am
Loss Contingency Accrual [Roll Forward]
Assumed in Acquisition		$ 0

Casualty, Environmental and O_4

Casualty, Environmental and Other Reserves - Balance Sheet Presentation (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Contingencies [Line Items]
Current	$ 144	$ 144
Long-term	296	292
Total	440	436	$ 368	$ 314
Casualty
Contingencies [Line Items]
Current	52	50
Long-term	143	144
Total	195	194	180	196
Personal Injury
Contingencies [Line Items]
Current	45	40
Long-term	83	86
Total	128	126
Occupational
Contingencies [Line Items]
Current	7	10
Long-term	60	58
Total	67	68
Environmental
Contingencies [Line Items]
Current	41	53
Long-term	113	108
Total	154	161	108	76
Other
Contingencies [Line Items]
Current	51	41
Long-term	40	40
Total	$ 91	$ 81	$ 80	$ 42

Casualty, Environmental and O_5

Casualty, Environmental and Other Reserves - Narrative (Details)	12 Months Ended
	Dec. 31, 2023 USD ($) claim site	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Loss Contingencies [Line Items]
Reserves	$ 440,000,000	$ 436,000,000	$ 368,000,000	$ 314,000,000
Casualty Reserves
Loss Contingencies [Line Items]
Reserves	195,000,000	194,000,000	180,000,000	196,000,000
Self-insured retention amount per injury	$ 100,000,000
Individual claims expected to exceed self-insured retention amount \| claim	0
Environmental
Loss Contingencies [Line Items]
Reserves	$ 154,000,000	161,000,000	108,000,000	76,000,000
Number of environmentally impaired sites \| site	230
Other
Loss Contingencies [Line Items]
Reserves	$ 91,000,000	$ 81,000,000	$ 80,000,000	$ 42,000,000

Properties - Schedule of Net Pr

Properties - Schedule of Net Properties (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 50,320	$ 48,105
Accumulated depreciation	(15,385)	(13,863)
Net book value	34,935	34,242
Total Road
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	36,590	34,792
Accumulated depreciation	(10,926)	(9,727)
Net book value	25,664	25,065
Rail and Other Track Material
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	9,537	8,660
Accumulated depreciation	(1,978)	(1,405)
Net book value	$ 7,559	$ 7,255
Annual depreciation rate	2.50%	2.50%
Estimated useful life (avg. years)	41 years	41 years
Ties
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 7,020	$ 6,763
Accumulated depreciation	(2,131)	(2,010)
Net book value	$ 4,889	$ 4,753
Annual depreciation rate	3.50%	3.50%
Estimated useful life (avg. years)	28 years	28 years
Grading
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 2,796	$ 2,741
Accumulated depreciation	(668)	(637)
Net book value	$ 2,128	$ 2,104
Annual depreciation rate	1.30%	1.30%
Estimated useful life (avg. years)	75 years	75 years
Ballast
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 3,424	$ 3,383
Accumulated depreciation	(1,119)	(1,130)
Net book value	$ 2,305	$ 2,253
Annual depreciation rate	2.60%	2.60%
Estimated useful life (avg. years)	38 years	38 years
Bridges, Trestles, and Culverts
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 3,121	$ 2,989
Accumulated depreciation	(525)	(454)
Net book value	$ 2,596	$ 2,535
Annual depreciation rate	1.70%	1.70%
Estimated useful life (avg. years)	60 years	60 years
Signals and Interlockers
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 3,376	$ 3,299
Accumulated depreciation	(1,351)	(1,210)
Net book value	$ 2,025	$ 2,089
Annual depreciation rate	4.10%	4.10%
Estimated useful life (avg. years)	24 years	24 years
Buildings
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 1,530	$ 1,416
Accumulated depreciation	(608)	(558)
Net book value	$ 922	$ 858
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	$ 5,786	$ 5,541
Accumulated depreciation	(2,546)	(2,323)
Net book value	$ 3,240	$ 3,218
Annual depreciation rate	4.10%	4.10%
Estimated useful life (avg. years)	25 years	25 years
Total Equipment
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 10,643	$ 10,296
Accumulated depreciation	(4,459)	(4,136)
Net book value	6,184	6,160
Locomotive
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	4,952	4,848
Accumulated depreciation	(1,981)	(1,856)
Net book value	$ 2,971	$ 2,992
Annual depreciation rate	3.80%	3.80%
Estimated useful life (avg. years)	26 years	26 years
Freight Cars
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 2,300	$ 2,316
Accumulated depreciation	(378)	(369)
Net book value	$ 1,922	$ 1,947
Annual depreciation rate	3.10%	3.10%
Estimated useful life (avg. years)	32 years	32 years
Work Equipment and Other
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 3,391	$ 3,132
Accumulated depreciation	(2,100)	(1,911)
Net book value	$ 1,291	$ 1,221
Annual depreciation rate	8.90%	8.90%
Estimated useful life (avg. years)	11 years	11 years
Land
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	$ 2,272	$ 2,272
Net book value	2,272	2,272
Construction In Progress
Property, Plant and Equipment, Net, by Type [Abstract]
Cost	815	745
Net book value	$ 815	$ 745

Properties - Narrative (Details

Properties - Narrative (Details) $ in Millions	12 Months Ended			21 Months Ended
Properties - Narrative (Details) $ in Millions	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2022 USD ($)	Mar. 26, 2021 property phase
Property, Plant and Equipment [Line Items]
Percentage of labor costs relating to the deconstruction of old track	20%
Percentage of labor costs relating to the installation of new track	80%
Percentage of assets depreciated under the group-life method	84%
Properties	$ 50,320	$ 48,105		$ 48,105
Gains on sale of properties	34	238	$ 454
Proceeds from property sale transaction	52	246	529
Gains	34	238	454
Impairment expense	$ 2	$ 4	2
Government Assistance, Statement of Income or Comprehensive Income [Extensible Enumeration]	Properties	Properties
Government assistance received	$ 84	$ 49
Non-freight accounts receivable	57	34
Equipment assets
Property, Plant and Equipment [Line Items]
Properties	$ 10,643	10,296		10,296
Life studies, frequency period	3 years
Equipment assets \| Service Life, Salvage Value And Other
Property, Plant and Equipment [Line Items]
Depreciation expense		80
Road and track assets
Property, Plant and Equipment [Line Items]
Properties	$ 36,590	34,792		34,792
Life studies, frequency period	6 years
Virginia Line Segments
Property, Plant and Equipment [Line Items]
Number of property rights for sale \| property					3
Number phases to complete property right sale transaction \| phase					3
Proceeds from property sale transaction	$ 0	125	400	525
Gains	$ 0	$ 144	$ 349	$ 493

Properties - Gain (Loss) on Sal

Properties - Gain (Loss) on Sale of Property Rights (Details) - USD ($) $ in Millions	12 Months Ended			21 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Gains	$ 34	$ 238	$ 454
Proceeds and Advances from Property Dispositions	52	246	529
Virginia Line Segments
Property, Plant and Equipment [Line Items]
Gains	0	144	349	$ 493
Proceeds and Advances from Property Dispositions	$ 0	$ 125	$ 400	$ 525

Leases - Narrative (Details)

Leases - Narrative (Details) $ in Millions	12 Months Ended
Leases - Narrative (Details) $ in Millions	Dec. 31, 2023 USD ($) mi	Dec. 31, 2022 USD ($)
Lessee, Lease, Description [Line Items]
Right of Use Asset	$ 498	$ 505
Right-of-use asset recognized as non-cash asset addition	56	74
Cash paid for amounts included in measurement of operating lease liabilities	$ 78	$ 76
State of Georgia
Lessee, Lease, Description [Line Items]
Term of lease agreement	50 years
Number of miles of right-of-way with integral equipment leased \| mi	137
Percentage of annual increase in operating lease	2.50%
Maximum \| Other parties
Lessee, Lease, Description [Line Items]
Term of lease agreement	50 years

Leases - Schedule of Informatio

Leases - Schedule of Information About Company's Operating Leases (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Maturity of Lease Liabilities
2024	$ 70
2025	67
2026	51
2027	43
2028	35
Thereafter	1,108
Total	1,374
Less: Imputed Interest	(815)
Present Value of Operating Lease Liabilities	$ 559	$ 557

Leases - Balance Sheet Classifi

Leases - Balance Sheet Classification and Other Information (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Balance Sheet Classification
Right of Use Asset	$ 498	$ 505
Current Lease Liabilities (Included in Other Current Liabilities)	68	69
Long-term Lease Liabilities	491	488
Total Operating Lease Liabilities	$ 559	$ 557
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other Current Liabilities	Other Current Liabilities
Other Information
Weighted-average Remaining Lease Term for Operating Leases	30 years	31 years
Weighted-average Discount Rate for Operating Leases	5.10%	5%

Leases - Operating Lease Costs

Leases - Operating Lease Costs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Leases [Abstract]
Rent Expense on Operating Leases	$ 109	$ 109	$ 89

Commitments and Contingencies -

Commitments and Contingencies - Schedule of Number of Locomotives and Payments under Long-term Maintenance Program (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Amounts Paid	$ 200	$ 168	$ 99
Cost, maintenance prepayments		$ 40

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Annual Payments under Long-term Maintenance Program (Details) $ in Millions	Dec. 31, 2023 USD ($)
Unrecorded Unconditional Purchase Obligation [Abstract]
2024	$ 524
2025	502
2026	434
2027	558
2028	435
Thereafter	1,279
Total	3,732
Locomotive Maintenance & Rebuild Payments
Unrecorded Unconditional Purchase Obligation [Abstract]
2024	342
2025	365
2026	397
2027	521
2028	402
Thereafter	1,223
Total	3,250
Other Commitments
Unrecorded Unconditional Purchase Obligation [Abstract]
2024	182
2025	137
2026	37
2027	37
2028	33
Thereafter	56
Total	$ 482

Commitments and Contingencies_3

Commitments and Contingencies - Narrative (Details)				1 Months Ended			12 Months Ended
Commitments and Contingencies - Narrative (Details)	Jan. 31, 2024 USD ($) party	Mar. 24, 2023 defendant	Mar. 02, 2023 mi	Jun. 30, 2018 defendant	Mar. 31, 2016 mi	May 31, 2007 entity claim	Dec. 31, 2023 USD ($) locomotive mi	Mar. 02, 2022 party
Operating Leased Assets [Line Items]
Number of locomotives under the long term maintenance plan \| locomotive							1,900
Non-catastrophic property deductible (up to)							$ 100,000,000
Casualty and catastrophic property deductible (up to)							$ 75,000,000
Fuel Surcharge Antitrust Litigation
Operating Leased Assets [Line Items]
Number of other U.S.-based entities mentioned in class action lawsuit \| entity						3
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
Site contingency, number of upper miles under study \| mi			9
Site contingency, number of parties liable \| party								8
Number of defendants \| defendant		37		110
Environmental Litigation \| Subsequent Event
Operating Leased Assets [Line Items]
Number of parties participating in modified CD \| party	82
Environmental Litigation \| Other Defendants \| Subsequent Event
Operating Leased Assets [Line Items]
Litigation settlement, amount awarded to other party	$ 150,000,000
Minimum \| Pending Litigation
Operating Leased Assets [Line Items]
Range of possible loss from legal proceedings							$ 3,000,000
Maximum \| Pending Litigation
Operating Leased Assets [Line Items]
Range of possible loss from legal proceedings							55,000,000
Casualty
Operating Leased Assets [Line Items]
Self-insured retention amount per occurrence (up to)							$ 100,000,000

Employee Benefit Plans - Narrat

Employee Benefit Plans - Narrative (Details)		12 Months Ended
Employee Benefit Plans - Narrative (Details)	Feb. 14, 2024 $ / shares	Dec. 31, 2023 USD ($) plan $ / shares	Dec. 31, 2022 USD ($) $ / shares	Dec. 31, 2021 USD ($) $ / shares
Defined Benefit Plan Disclosure [Line Items]
Employer contributions		$ 0	$ 0	$ 0
Expected contributions expected in the next fiscal year		$ 0
Percentage within which the planned allocation is managed		5%
Investments at Fair Value		$ 2,422,000,000	$ 2,327,000,000
Common stock dividends, per share (in dollars per share) \| $ / shares		$ 0.44	$ 0.40	$ 0.37
Subsequent Event
Defined Benefit Plan Disclosure [Line Items]
Increase in quarterly cash dividend percentage	9%
Common stock dividends, per share (in dollars per share) \| $ / shares	$ 0.12
Growth-Oriented
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of pension plan assets		55%
Investments at Fair Value		$ 1,271,000,000	$ 1,434,000,000
Immunizing
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage of pension plan assets		45%
Investments at Fair Value		$ 1,151,000,000	893,000,000
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Employer contributions		20,000,000	18,000,000
Net actuarial gain (loss)		$ (20,000,000)	$ 570,000,000
Increase (decrease) in weighted average discount rate		0.20%	(2.24%)
Investments at Fair Value		$ 2,422,000,000	$ 2,327,000,000	$ 3,016,000,000
Pre-tax (loss) gain to be amortized related to post-retirement obligations		(623,000,000)
Plan benefit accruals		2,343,000,000	2,368,000,000	3,022,000,000
Defined benefit plan, service cost		24,000,000	32,000,000	41,000,000
Accumulated Benefit Obligation		$ 2,252,000,000	2,285,000,000
Pension Plan \| Quality Carriers, Inc. \| Multiemployer Plan, Union-represented Employees
Defined Benefit Plan Disclosure [Line Items]
Number of multi-employer pension plans \| plan		2
Contingent liability for full withdrawal or termination of multi-employer plan		$ 334,000,000
Pension Plan \| Quality Carriers, Inc. \| Multiemployer Plan, Union-represented Employees, Central Southeast and Southwest Areas Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Contingent liability for full withdrawal or termination of multi-employer plan		328,000,000
Postretirement Health Coverage
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, expected future benefit payments		50,000,000
Accumulated Benefit Obligation		56,000,000	61,000,000
Other Postretirement Benefits Plan
Defined Benefit Plan Disclosure [Line Items]
Premium expense incurred under the plan		11,000,000	13,000,000	21,000,000
Savings Plan
Defined Benefit Plan Disclosure [Line Items]
Expense associated with savings plans		$ 35,000,000	$ 28,000,000	$ 29,000,000

Employee Benefit Plans - Summar

Employee Benefit Plans - Summary of Participants (Details) - Pension Plan	Jan. 01, 2023 employee
Defined Benefit Plan Disclosure [Line Items]
Active Employees	2,479
Retirees and Beneficiaries	11,294
Other	3,504
Total	17,277

Employee Benefit Plans - Schedu

Employee Benefit Plans - Schedule of Future Expected Benefit Payments (Details) - Pension Benefits $ in Millions	Dec. 31, 2023 USD ($)
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
2024	$ 190
2025	186
2026	183
2027	182
2028	181
2029-2033	870
Total	$ 1,792

Employee Benefit Plans - Sche_2

Employee Benefit Plans - Schedule of Allocation of Plan Assets (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Plan Disclosure [Line Items]
Amount	$ 2,422	$ 2,327
Percent of total assets	100%	100%
Growth-Oriented
Defined Benefit Plan Disclosure [Line Items]
Amount	$ 1,271	$ 1,434
Percent of total assets	52%	62%
Equity
Defined Benefit Plan Disclosure [Line Items]
Amount	$ 1,142	$ 1,249
Percent of total assets	47%	54%
Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Amount	$ 114	$ 144
Percent of total assets	4%	6%
Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Amount	$ 15	$ 41
Percent of total assets	1%	2%
Immunizing
Defined Benefit Plan Disclosure [Line Items]
Amount	$ 1,151	$ 893
Percent of total assets	48%	38%
Fixed Income
Defined Benefit Plan Disclosure [Line Items]
Amount	$ 911	$ 777
Percent of total assets	38%	33%
Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Amount	$ 240	$ 116
Percent of total assets	10%	5%

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, 2023	Dec. 31, 2022	Dec. 31, 2021
Change in Plan Assets:
Fair Value of Plan Assets at Beginning of Plan Year	$ 2,327,000,000
Non-qualified Employer Contributions	0	$ 0	$ 0
Fair Value of Plan Assets at End of Plan Year	2,422,000,000	2,327,000,000
Capitalized service costs	4,000,000	4,000,000
Pension Benefits
Actuarial Present Value of Benefit Obligation
Accumulated Benefit Obligation	2,252,000,000	2,285,000,000
Projected Benefit Obligation	2,343,000,000	2,368,000,000	3,022,000,000
Change in Projected Benefit Obligation:
Projected Benefit Obligation at Beginning of Plan Year	2,368,000,000	3,022,000,000
Service Cost	28,000,000	36,000,000
Interest Cost	111,000,000	64,000,000	55,000,000
Actuarial Loss (Gain)	20,000,000	(570,000,000)
Benefits Paid	(184,000,000)	(184,000,000)
Benefit Obligation at End of Plan Year	2,343,000,000	2,368,000,000	3,022,000,000
Change in Plan Assets:
Fair Value of Plan Assets at Beginning of Plan Year	2,327,000,000	3,016,000,000
Actual Return (Loss) on Plan Assets	259,000,000	(523,000,000)
Non-qualified Employer Contributions	20,000,000	18,000,000
Benefits Paid	(184,000,000)	(184,000,000)
Fair Value of Plan Assets at End of Plan Year	2,422,000,000	2,327,000,000	$ 3,016,000,000
Funded Status at End of Plan Year	$ 79,000,000	$ (41,000,000)

Employee Benefit Plans - Sche_4

Employee Benefit Plans - Schedule of Amount Recognized in Balance Sheet (Details) - Pension Benefits - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Amounts Recorded in Consolidated Balance Sheets [Abstract]
Long-term Assets	$ 277	$ 164
Current Liabilities	(16)	(17)
Long-term Liabilities	(182)	(188)
Net Amount Recognized in Consolidated Balance Sheets	$ 79	$ (41)

Employee Benefit Plans - Benefi

Employee Benefit Plans - Benefit Obligations in Excess of Plan Assets (Details) $ in Millions	Dec. 31, 2023 USD ($)
Projected Benefit Obligation
Aggregate fair value of plan assets	$ 0
Aggregate benefit obligation	(198)
Accumulated Benefit Obligation
Aggregate fair value of plan assets	0
Aggregate benefit obligation	$ (188)

Employee Benefit Plans - Net Be

Employee Benefit Plans - Net Benefit Expense Recorded on the Income Statement (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Components of expense/ (income) related to net benefit expense [Abstract]
Total Income Included in Other Income - Net	$ (29)	$ (79)	$ (64)
Pension Benefits
Components of expense/ (income) related to net benefit expense [Abstract]
Service Cost Included in Labor and Fringe	24	32	41
Interest Cost	111	64	55
Expected Return on Plan Assets	(164)	(188)	(186)
Amortization of Net Loss	29	50	73
Total Income Included in Other Income - Net	(24)	(74)	(58)
Net Periodic Benefit Cost (Credit)	0	(42)	(17)
Settlement Loss	0	1	0
Total Periodic Benefit Cost (Credit)	$ 0	$ (41)	$ (17)

Employee Benefit Plans - Sche_5

Employee Benefit Plans - Schedule of Pre-tax Change in Other Comprehensive Loss (Income) (Details) - Pension Benefits - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Recognized in the Balance Sheet
(Gains) Losses	$ (75)	$ 141
Expense Recognized in the Income Statement
Amortization of Net Loss	29	50	$ 73
Settlement Loss	$ 0	$ 1	$ 0

Employee Benefit Plans - Sche_6

Employee Benefit Plans - Schedule of Weighted-Average Assumptions Used (Details) - Pension Benefits	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
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%
Discount Rates:
Service Cost for Plan Year	5.09%	2.98%
Interest Cost for Plan Year	4.90%	2.18%
Benefit Obligation at End of Plan Year	4.82%	5.02%
Salary Scale Inflation	4.80%	4.80%
Cash Balance Plan Interest Credit Rate	3.75%	3.75%

Debt and Credit Agreements - Sc

Debt and Credit Agreements - Schedule of Long-term Debt Instruments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Finance Leases Average Interest Rate	5.90%
Subtotal Long-term Debt (Including Current Portion)	$ 18,533	$ 18,047
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Long-term Debt (Excluding Current Portion)	Long-term Debt (Excluding Current Portion)
Finance Leases	$ 17	$ 29
Less Debt Due within One Year	(558)	(151)
Long-term Debt (Excluding Current Portion)	$ 17,975	17,896
Notes
Debt Instrument [Line Items]
Debt Average Interest Rates	4.20%
Subtotal Long-term Debt (Including Current Portion)	$ 18,514	17,877
Equipment Obligations
Debt Instrument [Line Items]
Debt Average Interest Rates	4.40%
Subtotal Long-term Debt (Including Current Portion)	$ 2	$ 141

Debt and Credit Agreements - Na

Debt and Credit Agreements - Narrative (Details)	3 Months Ended					12 Months Ended
Debt and Credit Agreements - Narrative (Details)	Dec. 31, 2023 USD ($) swap	Sep. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)	Mar. 31, 2022 USD ($) swap	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Sep. 07, 2023 USD ($)	Jul. 28, 2022 USD ($)	Jul. 01, 2021 USD ($)	Dec. 31, 2020 USD ($)
Debt Instrument [Line Items]
Notional Value of Hedged Notes								$ 0
Other Operating Activities						$ (5,000,000)	$ (17,000,000)	$ 12,000,000
Quality Carriers, Inc.
Debt Instrument [Line Items]
Finance lease obligations and debt assumed											$ 68,000,000
Interest Rate Swap \| Cash Flow Hedging \| Designated as Hedging Instrument
Debt Instrument [Line Items]
Interest rate fair value hedge asset at fair value	$ 48,000,000			$ 127,000,000		48,000,000	127,000,000
Derivative asset, notional value	114,000,000			340,000,000		114,000,000	340,000,000					$ 500,000,000
Cash flow hedge derivative instrument assets at fair value	$ 48,000,000			127,000,000		48,000,000	127,000,000
Notional amount settled		$ 113,000,000	$ 113,000,000	160,000,000
Derivative, cash received on hedge				52,000,000
Other Operating Activities		$ 51,000,000	$ 44,000,000
2023 Fixed-to-Floating Interest Rate Swaps \| Fair Value Hedging
Debt Instrument [Line Items]
Derivative, number of fair value hedges \| swap	2
Derivative, term of contract	10 years
2023 Fixed-to-Floating Interest Rate Swaps \| Fair Value Hedging \| Designated as Hedging Instrument
Debt Instrument [Line Items]
Interest rate fair value hedge asset at fair value	$ 19,000,000					19,000,000
2022 Fixed-to-Floating Interest Rate Swap \| Fair Value Hedging
Debt Instrument [Line Items]
Derivative, number of fair value hedges \| swap					5
Derivative, term of contract					10 years
2022 Fixed-to-Floating Interest Rate Swap \| Fair Value Hedging \| Designated as Hedging Instrument
Debt Instrument [Line Items]
Interest rate fair value hedge liability at fair value	107,000,000			118,000,000		107,000,000	118,000,000
Commercial Paper
Debt Instrument [Line Items]
Line of credit facility capacity	1,000,000,000					1,000,000,000
Line of credit amount outstanding	0					0
3.25% Notes Due 2027
Debt Instrument [Line Items]
Notional Value of Hedged Notes	$ 850,000,000					$ 850,000,000
Interest rate	3.25%					3.25%
Unsecured Revolving Credit Facility Expiring March 2024 \| Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility capacity				1,200,000,000			1,200,000,000
Line of credit facility, amount outstanding	$ 0					$ 0
4.1% Notes Due 2032
Debt Instrument [Line Items]
Notional Value of Hedged Notes										$ 950,000,000
Interest rate										4.10%
4.5% Notes Due 2052
Debt Instrument [Line Items]
Notional Value of Hedged Notes										$ 900,000,000
Interest rate										4.50%
4.65% Notes Due 2068
Debt Instrument [Line Items]
Notional Value of Hedged Notes										$ 150,000,000
Interest rate										4.65%
Fixed Rate Notes Due Between 2036 and 2040
Debt Instrument [Line Items]
Notional Value of Hedged Notes	1,050,000,000			$ 800,000,000	$ 800,000,000	1,050,000,000	$ 800,000,000
Fixed Rate Notes Due 2033
Debt Instrument [Line Items]
Notional Value of Hedged Notes	250,000,000					250,000,000
5.2% Notes Due 2033
Debt Instrument [Line Items]
Notional Value of Hedged Notes									$ 600,000,000
Interest rate									5.20%
Unsecured Revolving Credit Facility Due 2028 \| Revolving Credit Facility
Debt Instrument [Line Items]
Line of credit facility capacity	$ 1,200,000,000					$ 1,200,000,000

Debt and Credit Agreements - _2

Debt and Credit Agreements - Schedule of Long-term Debt Maturities (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Maturities of Long-term Debt [Abstract]
2024	$ 558
2025	606
2026	704
2027	998
2028	1,001
Thereafter	14,666
Subtotal Long-term Debt (Including Current Portion)	$ 18,533	$ 18,047

Debt and Credit Agreements - _3

Debt and Credit Agreements - Schedule of Interest Rate Derivatives (Details) - USD ($)	Dec. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Notional Value of Hedged Notes				$ 0
Fixed-to-Floating Interest Rate Swap \| Fair Value Hedging \| Designated as Hedging Instrument
Debt Instrument [Line Items]
Fair Value Asset Adjustment to Hedged Notes	$ 19,000,000	$ 0
Fair Value Liability Adjustment to Hedged Notes	(107,000,000)	(118,000,000)
Carrying Amount of Hedged Notes	962,000,000	682,000,000
Fixed Rate Notes Due Between 2036 and 2040
Debt Instrument [Line Items]
Notional Value of Hedged Notes	$ 1,050,000,000	$ 800,000,000	$ 800,000,000

Debt and Credit Agreements - In

Debt and Credit Agreements - Interest Expense Impact (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Fixed-to-Floating Interest Rate Swaps
Derivative [Line Items]
Interest Expense Impact (Increase) Decrease	$ (28)	$ (1)

Debt and Credit Agreements - Un

Debt and Credit Agreements - Unrealized Amounts Related to Cash Flow Hedges (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash Flow Hedging
Derivative [Line Items]
Unrealized Gain - Net	$ 0	$ 80	$ 8

Revenues - Disaggregated by Lin

Revenues - Disaggregated by Lines of Business (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Revenue	$ 14,657	$ 14,853	$ 12,522
Total Merchandise
Disaggregation of Revenue [Line Items]
Revenue	8,653	8,239	7,539
Chemicals
Disaggregation of Revenue [Line Items]
Revenue	2,599	2,584	2,421
Agricultural and Food Products
Disaggregation of Revenue [Line Items]
Revenue	1,657	1,664	1,461
Automotive
Disaggregation of Revenue [Line Items]
Revenue	1,219	1,054	886
Forest Products
Disaggregation of Revenue [Line Items]
Revenue	1,012	996	918
Metals and Equipment
Disaggregation of Revenue [Line Items]
Revenue	917	828	796
Minerals
Disaggregation of Revenue [Line Items]
Revenue	733	658	587
Fertilizers
Disaggregation of Revenue [Line Items]
Revenue	516	455	470
Coal
Disaggregation of Revenue [Line Items]
Revenue	2,484	2,434	1,790
Intermodal
Disaggregation of Revenue [Line Items]
Revenue	2,060	2,306	2,039
Trucking
Disaggregation of Revenue [Line Items]
Revenue	882	966	410
Other
Disaggregation of Revenue [Line Items]
Revenue	$ 578	$ 908	$ 744

Revenues - Narrative (Details)

Revenues - Narrative (Details)	12 Months Ended
Revenues - Narrative (Details)	Dec. 31, 2023
Concentration Risk [Line Items]
Payment period after invoice date	15 days
Minimum
Concentration Risk [Line Items]
Average transit time to complete a rail shipment	2 days
Maximum
Concentration Risk [Line Items]
Average transit time to complete a rail shipment	7 days

Revenues - Accounts Receivables

Revenues - Accounts Receivables, Net (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total Accounts Receivable, net	$ 1,393	$ 1,313
Freight Receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts Receivables, gross	1,047	1,067
Allowance for Credit Losses	(18)	(16)
Total Accounts Receivable, net	1,029	1,051
Non-Freight Receivables
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accounts Receivables, gross	378	279
Allowance for Credit Losses	(14)	(17)
Total Accounts Receivable, net	$ 364	$ 262

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
Income Taxes - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Earnings before income taxes	$ 4,891	$ 5,414	$ 4,951
Additional income tax benefit	22	78	$ 48
Unrecognized tax benefits	19	18
Amount of unrecognized tax benefits that could favorably impact effective income tax rate	$ 15	$ 14

Income Taxes - Breakdown of Inc

Income Taxes - Breakdown of Income Tax Expense Between Current and Deferred (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Current:
Federal	$ 852	$ 928	$ 827
State	184	203	176
Subtotal Current	1,036	1,131	1,003
Deferred:
Federal	122	166	166
State	18	(49)	1
Subtotal Deferred	140	117	167
Total Income Tax Expense	$ 1,176	$ 1,248	$ 1,170

Income Taxes - Income Tax Expen

Income Taxes - Income Tax Expense Reconciled to Tax Computed at Statutory Rates (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Expense
Federal Income Taxes	$ 1,027	$ 1,137	$ 1,040
State Income Taxes	153	121	139
Other	(4)	(10)	(9)
Total Income Tax Expense	$ 1,176	$ 1,248	$ 1,170
Rate
Federal Income Taxes	21%	21%	21%
State Income Taxes	3.10%	2.20%	2.80%
Other	(0.10%)	(0.10%)	(0.20%)
Income Tax Rate	24%	23.10%	23.60%

Income Taxes - Schedule of Sign

Income Taxes - Schedule of Significant Components of Deferred Income Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Assets
Other Employee Benefit Plans	$ 103	$ 105
Other	459	553
Total	562	658
Liabilities
Accelerated Depreciation	7,678	7,600
Other	630	627
Total	8,308	8,227
Net Deferred Income Tax Liabilities	$ 7,746	$ 7,569

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Fair Value of Investment Assets (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities	$ 181	$ 196
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Amortized Cost	184	201
Level 1 \| Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	80	89
Level 1 \| Fair Value \| Fixed Income Mutual Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities	80	89
Level 1 \| Fair Value \| Corporate Bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities	0	0
Level 1 \| Fair Value \| Government Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities	0	0
Level 2 \| Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	101	107
Level 2 \| Fair Value \| Fixed Income Mutual Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities	0	0
Level 2 \| Fair Value \| Corporate Bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities	60	49
Level 2 \| Fair Value \| Government Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities	41	58
Total \| Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Investments at Fair Value	181	196
Total \| Fair Value \| Fixed Income Mutual Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities	80	89
Total \| Fair Value \| Corporate Bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities	60	49
Total \| Fair Value \| Government Securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Securities	$ 41	$ 58

Fair Value Measurements - Sch_2

Fair Value Measurements - Schedule of Investment Maturities (Details) - Fair Value - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Less than 1 year	$ 83	$ 129
1 - 5 years	37	24
5 - 10 years	17	10
Greater than 10 years	44	33
Total investments at fair value	$ 181	$ 196

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Interest Rate Swap \| Cash Flow Hedging \| Designated as Hedging Instrument
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate fair value hedge asset at fair value	$ 48	$ 127
Fixed-to-Floating Interest Rate Swaps \| Fair Value Hedging \| Designated as Hedging Instrument
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate fair value hedge liability at fair value	107	$ 118
2023 Fixed-to-Floating Interest Rate Swaps \| Fair Value Hedging \| Designated as Hedging Instrument
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate fair value hedge asset at fair value	$ 19
Partnerships
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Net asset value, redemption restriction period	15 days
Commingled and Common Collective Trust Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Net asset value, redemption restriction period	45 days

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, 2023	Dec. 31, 2022
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term Debt (Including Current Maturities):	$ 17,528	$ 16,135
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term Debt (Including Current Maturities):	$ 18,533	$ 18,047

Fair Value Measurements - Sch_4

Fair Value Measurements - Schedule of Pension Plan Assets at Fair Value by Level (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	$ 2,422	$ 2,327
Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	2,422	2,327	$ 3,016
Pension Plan \| Total
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	1,409	1,265
Pension Plan \| Total \| Common Stock
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	340	335
Pension Plan \| Total \| Mutual Funds
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	32	29
Pension Plan \| Total \| Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	255	157
Pension Plan \| Total \| Corporate Bonds
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	646	647
Pension Plan \| Total \| Government Securities
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	126	88
Pension Plan \| Total \| Asset-backed Securities, Derivatives and Other
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	10	9
Pension Plan \| Level 1
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	627	521
Pension Plan \| Level 1 \| Common Stock
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	340	335
Pension Plan \| Level 1 \| Mutual Funds
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	32	29
Pension Plan \| Level 1 \| Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	255	157
Pension Plan \| Level 1 \| Corporate Bonds
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	0	0
Pension Plan \| Level 1 \| Government Securities
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	0	0
Pension Plan \| Level 1 \| Asset-backed Securities, Derivatives and Other
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	0	0
Pension Plan \| Level 2
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	782	744
Pension Plan \| Level 2 \| Common Stock
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	0	0
Pension Plan \| Level 2 \| Mutual Funds
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	0	0
Pension Plan \| Level 2 \| Cash and Cash Equivalents
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	0	0
Pension Plan \| Level 2 \| Corporate Bonds
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	646	647
Pension Plan \| Level 2 \| Government Securities
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	126	88
Pension Plan \| Level 2 \| Asset-backed Securities, Derivatives and Other
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	10	9
Pension Plan \| Investments measured at net asset value
Defined Benefit Plan Disclosure [Line Items]
Investments at Fair Value	$ 1,013	$ 1,062

Other Income - Net (Details)

Other Income - Net (Details) - USD ($) $ in Millions	12 Months Ended
Other Income - Net (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Other Income and Expenses [Abstract]
Net Periodic Pension and Post-retirement Benefit Credit	$ 29	$ 79	$ 64
Interest Income	79	42	7
Miscellaneous Income	31	12	8
Total Other Income - Net	$ 139	$ 133	$ 79

Investment in Affiliates and _3

Investment in Affiliates and Related-Party Transactions - Equity-method Investments in Affiliates (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Related Party Transaction [Line Items]
Total	$ 2,397	$ 2,292
Corporate Joint Venture \| Conrail
Related Party Transaction [Line Items]
Total	1,175	1,124
Affiliated Entity
Related Party Transaction [Line Items]
Total	2,397	2,292
Affiliated Entity \| TTX
Related Party Transaction [Line Items]
Total	961	914
Affiliated Entity \| Oher Equity Method and Cost Method Investments
Related Party Transaction [Line Items]
Total	$ 261	$ 254

Investment in Affiliates and _4

Investment in Affiliates and Related-Party Transactions - Narrative (Details) $ in Millions	1 Months Ended	12 Months Ended
	Dec. 31, 2020 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2014 note
Corporate Joint Venture \| Conrail
Related Party Transaction [Line Items]
Ownership percentage		42%
Voting interest percentage		50%
Difference between carrying amount and underlying equity		$ 323
Promissory notes executed \| note						2
Previous notes converted in non-cash transaction	$ 217
Interest expense		$ 6	$ 6	$ 6
Corporate Joint Venture \| Conrail \| Long-term Debt \| 1.31% Promissory Note Due December 2050
Related Party Transaction [Line Items]
Note interest rate					1.31%
New notes issued in non-cash transaction					$ 441
Corporate Joint Venture \| Conrail \| Long-term Debt \| 2.89% Promissory Note Due October 2044
Related Party Transaction [Line Items]
Previous notes converted in non-cash transaction	$ 224
Converted instrument, rate	2.89%
Related Party \| TTX
Related Party Transaction [Line Items]
Ownership percentage		20%

Investment in Affiliates and _5

Investment in Affiliates and Related-Party Transactions - Schedule of Future Payments Due under Operating Leases (Details) $ in Millions	Dec. 31, 2023 USD ($)
Related Party Transaction [Line Items]
2024	$ 70
2025	67
2026	51
2027	43
2028	35
Thereafter	1,108
Total	1,374
Corporate Joint Venture \| Conrail
Related Party Transaction [Line Items]
2024	32
2025	32
2026	32
2027	32
2028	32
Thereafter	13
Total	$ 173

Investment in Affiliates and _6

Investment in Affiliates and Related-Party Transactions - Schedule of Related Party in the Consolidated Income Statement Components (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Related Party Amounts Consolidated Income Statements [Abstract]
Total Expense	$ 9,096	$ 8,830	$ 6,928
Corporate Joint Venture \| Conrail
Related Party Amounts Consolidated Income Statements [Abstract]
Rents, Fees and Services	132	130	128
Purchase Price Amortization and Other	4	4	4
Equity Earnings in Affiliates	(54)	(44)	(44)
Total Expense	82	90	88
Related Party \| TTX
Related Party Amounts Consolidated Income Statements [Abstract]
Equity Earnings in Affiliates	(49)	(51)	(52)
Car Hire Rents	249	241	221
Total Expense	$ 200	$ 190	$ 169

Investment in Affiliates and _7

Investment in Affiliates and Related-Party Transactions - Schedule of Related Party Consolidated Balance Sheet Components (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Corporate Joint Venture \| Conrail
Related Party Transaction [Line Items]
Accounts payable	$ 154	$ 136
Corporate Joint Venture \| Conrail \| 1.31% CSX Promissory Note due December 2050
Related Party Transaction [Line Items]
Notes payable	$ 73	$ 73
Promissory note interest rate	1.31%	1.31%
Corporate Joint Venture \| Conrail \| 1.31% CSXT Promissory Note due December 2050
Related Party Transaction [Line Items]
Notes payable	$ 368	$ 368
Promissory note interest rate	1.31%	1.31%
Related Party \| TTX
Related Party Transaction [Line Items]
Accounts payable	$ 43	$ 38

Other Comprehensive Income (L_3

Other Comprehensive Income (Loss) - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Equity [Abstract]
Comprehensive earnings	$ 3,791	$ 4,186	$ 3,971

Other Comprehensive Income (L_4

Other Comprehensive Income (Loss) - Changes in AOCI Balance by Components (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Other Comprehensive Income (Loss):
Income Before Reclassifications		$ 91	$ (41)	$ 158
Amounts Reclassified to Net Earnings		23	46	81
Tax Benefit (Expense)		(38)	15	(49)
Total Other Comprehensive Income (Note 16)		76	20	190
Pension and Other Post-Employment Benefits
Other Comprehensive Income (Loss):
Beginning Balance		(497)	(431)	(598)
Income Before Reclassifications		75	(129)	147
Amounts Reclassified to Net Earnings		18	44	66
Tax Benefit (Expense)		(19)	19	(46)
Total Other Comprehensive Income (Note 16)		74	(66)	167
Ending Balance		(423)	(497)	(431)
Interest Rate Derivatives
Other Comprehensive Income (Loss):
Beginning Balance		150	70	62
Income Before Reclassifications		16	88	11
Amounts Reclassified to Net Earnings		0	0	0
Tax Benefit (Expense)		(16)	(8)	(3)
Total Other Comprehensive Income (Note 16)		0	80	8
Ending Balance		150	150	70
Other
Other Comprehensive Income (Loss):
Beginning Balance		(41)	(47)	(62)
Income Before Reclassifications		0	0	0
Amounts Reclassified to Net Earnings		5	2	15
Tax Benefit (Expense)		(3)	4	0
Total Other Comprehensive Income (Note 16)		2	6	15
Ending Balance		(39)	(41)	(47)
Accumulated Other Comprehensive (Loss) Income
Other Comprehensive Income (Loss):
Beginning Balance		(388)	(408)	(598)
Total Other Comprehensive Income (Note 16)	[1]	76	20	190
Ending Balance		$ (312)	$ (388)	$ (408)

[1]Accumulated Other Comprehensive Loss year-end balances shown above are net of tax. The associated taxes were $84 million, $122 million, and $107 million for 2023, 2022 and 2021, respectively. For additional information see Note 16, Other Comprehensive Income (Loss).

Business Combinations - Narrati

Business Combinations - Narrative (Details) $ in Millions			3 Months Ended	12 Months Ended		22 Months Ended
Business Combinations - Narrative (Details) $ in Millions	Jun. 01, 2022 USD ($) mi	Jul. 01, 2021 USD ($) terminalAndFacility	Dec. 31, 2020 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Sep. 30, 2022 USD ($)	Dec. 31, 2023 mi
Business Acquisition [Line Items]
Number of rail route miles \| mi							20,000
Pan Am Systems, Inc.
Business Acquisition [Line Items]
Business combination, consideration transferred	$ 600
Business combination, consideration transferred, equity interests issued and issuable	422
Cash paid for acquisition	178
Deposit paid to acquire business classified as other investing activities			$ 30
Properties acquired	$ 600
Acquisition related costs				$ 22	$ 10	$ 32
Pan Am Systems, Inc. \| Pan Am Systems, Inc.
Business Acquisition [Line Items]
Number of rail route miles \| mi	1,200
Number of partial interests in rail route miles (more than) \| mi	600
Quality Carriers, Inc.
Business Acquisition [Line Items]
Cash paid for acquisition		$ 544
Cash and cash equivalents acquired		3
Properties acquired		225
Acquisition related costs		$ 17
Quality Carriers, Inc. \| Quality Carriers, Inc. \| United States, Canada and Mexico
Business Acquisition [Line Items]
Number of terminals and facilities (over) \| terminalAndFacility		100

Business Combinations - Allocat

Business Combinations - Allocation of Total Consideration to Fair Value of Assets and Liabilities of Quality Carriers (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Jun. 01, 2022	Dec. 31, 2021	Jul. 01, 2021
Assets Acquired:
Goodwill	$ 325	$ 319		$ 276
Pan-Am
Assets Acquired:
Accounts Receivable, net			$ 46
Properties and Equipment, net			600
Goodwill			17
Intangible Assets			90
Other Assets			11
Total Assets Acquired			764
Liabilities Assumed:
Accounts Payable and Accrued Liabilities			32
Deferred Tax Liabilities			75
Other Long-term Liabilities			57
Total Liabilities Assumed			164
Fair Value of Assets Acquired, Net of Liabilities Assumed:			$ 600
Quality Carriers
Assets Acquired:
Cash and Cash Equivalents					$ 3
Accounts Receivable, net					113
Properties and Equipment, net					225
Goodwill					213
Intangible Assets					180
Other Assets					9
Total Assets Acquired					743
Liabilities Assumed:
Accounts Payable and Accrued Liabilities					48
Finance Lease Obligations and Notes Payable					68
Casualty, Environmental and Other Reserves					62
Other Long-term Liabilities					21
Total Liabilities Assumed					199
Fair Value of Assets Acquired, Net of Liabilities Assumed:					$ 544

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets - Schedule of Goodwill and Other Intangible Asset Balances (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Goodwill
Beginning balance	$ 319	$ 276
Additions	6	43
Ending balance	325	319
Intangible Assets
Beginning balance, cost	198	180
Additions	8	18
Ending balance, cost	206	198
Beginning balance, accumulated amortization	(15)	(5)
Amortization	(10)	(10)
Ending balance, accumulated amortization	(25)	(15)
Net Carrying Amount	181	183	$ 175
Total Goodwill and Other Intangible Assets - Net
Beginning balance	502	451
Additions	14	61
Amortization	(10)	(10)
Ending balance	$ 506	$ 502

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets - Narrative (Details) - USD ($)			3 Months Ended	12 Months Ended
	Jun. 01, 2022	Jul. 01, 2021	Dec. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Finite-Lived Intangible Assets [Line Items]
Additions				$ 6,000,000	$ 43,000,000
Goodwill			$ 325,000,000	325,000,000	319,000,000	$ 276,000,000
Intangible assets acquired				8,000,000	18,000,000
Quality Carriers, Inc.
Finite-Lived Intangible Assets [Line Items]
Goodwill		$ 213,000,000
Intangible assets acquired		180,000,000
Goodwill impairment			$ 0
Quality Carriers, Inc. \| Customer Relationships
Finite-Lived Intangible Assets [Line Items]
Intangible assets acquired		$ 150,000,000
Amortization period of intangible assets acquired		20 years
Quality Carriers, Inc. \| Trade Names
Finite-Lived Intangible Assets [Line Items]
Intangible assets acquired		$ 30,000,000
Amortization period of intangible assets acquired		15 years
Pan-Am
Finite-Lived Intangible Assets [Line Items]
Additions	$ 17,000,000
Goodwill	$ 17,000,000
Several Acquisitions \| Quality Carriers, Inc.
Finite-Lived Intangible Assets [Line Items]
Additions				6,000,000	26,000,000
Intangible assets acquired				$ 8,000,000	$ 18,000,000