Enable Midstream Partners (ENBL) 10-Q6 May 202020 Q1 Quarterly reportFinancial data

Company Profile

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Mar. 31, 2020	Apr. 17, 2020
Entity Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Entity File Number	1-36413
Entity Registrant Name	ENABLE MIDSTREAM PARTNERS, LP
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	72-1252419
Entity Address, Address Line One	499 West Sheridan Avenue,
Entity Address, Address Line Two	Suite 1500
Entity Address, City or Town	Oklahoma City,
Entity Address, State or Province	OK
Entity Address, Postal Zip Code	73102
City Area Code	405
Local Phone Number	525-7788
Title of 12(b) Security	Common Units Representing Limited Partner Interests
Trading Symbol	ENBL
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Shell Company	false
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Entity Central Index Key	0001591763
Entity Common Stock, Shares Outstanding		435,448,437
Current Fiscal Year End Date	--12-31
Document Period End Date	Mar. 31, 2020

Condensed Consolidated Statemen

Condensed Consolidated Statements of Income (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Revenues (including revenues from affiliates (Note 13)):
Total Revenues	$ 648	$ 795
Cost and Expenses (including expenses from affiliates (Note 13)):
Cost of natural gas and natural gas liquids (excluding depreciation and amortization shown separately)	226	378
Operation and maintenance	102	103
General and administrative	24	26
Depreciation and amortization	104	105
Impairments (Note 7)	28	0
Impairment of Long-Lived Assets to be Disposed of		0
Taxes other than income tax	18	18
Total Cost and Expenses	502	630
Operating Income	146	165
Other Income (Expense):
Interest expense	(47)	(46)
Equity in earnings of equity method affiliate	6	3
Total Other Expense	(41)	(43)
Income Before Income Tax
Income Before Income Tax	105	122
Income tax benefit	0	(1)
Net Income
Net Income	105	123
Less: Net (loss) income attributable to noncontrolling interest
Less: Net (loss) income attributable to noncontrolling interest	(7)	1
Net Income Attributable to Limited Partners
Net Income Attributable to Limited Partners	112	122
Less: Series A Preferred Unit distributions (Note 6)
Less: Series A Preferred Unit distributions (Note 6)	9	9
Net Income Attributable to Common Units (Note 5)
Net Income Attributable to Common Units (Note 5)	103	113
Common Units
Net Income Attributable to Common Units (Note 5)
Net Income Attributable to Common Units (Note 5)	$ 103	$ 113
Basic and Diluted earnings (loss) per unit and weighted average number of units outstanding
Basic earnings per unit (Note 5)	$ 0.24	$ 0.26
Diluted earnings per unit (Note 5)	$ 0.19	$ 0.26
Product
Revenues (including revenues from affiliates (Note 13)):
Total Revenues	$ 288	$ 443
Natural Gas, Gathering, Transportation, Marketing and Processing
Revenues (including revenues from affiliates (Note 13)):
Total Revenues	$ 360	$ 352

Condensed Consolidated Statem_2

Condensed Consolidated Statement of Comprehensive Income (Unaudited) Statement - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 105	$ 123
Other comprehensive loss:
Unrealized losses on derivative instruments	(6)	0
Reclassification of derivative losses to net income	0	0
Other comprehensive loss	(6)	0
Comprehensive income	106	122
Less: Comprehensive (loss) income attributable to noncontrolling interest	(7)	1
Comprehensive income attributable to Limited Partners	$ 99	$ 123

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Current Assets:
Cash and cash equivalents	$ 4	$ 4
Restricted cash	0
Accounts receivable, net of allowance for doubtful accounts (Note 1)	192	244
Accounts receivable—affiliated companies	17	25
Inventory	43	46
Gas imbalances	36	35
Other current assets	41	35
Total current assets	333	389
Property, Plant and Equipment:
Property, plant and equipment	13,183	13,161
Less: Accumulated depreciation and amortization	2,366	2,291
Property, plant and equipment, net	10,817	10,870
Other Assets:
Intangible assets, net	585	601
Goodwill	0	12
Investment in equity method affiliate	305	309
Other, net of allowance for doubtful accounts (Note 1)	77	85
Total other assets	967	1,007
Total Assets	12,117	12,266
Current Liabilities:
Accounts payable	100	161
Accounts payable—affiliated companies	2	1
Current portion of long-term debt	0	251
Short-term debt	110	155
Taxes accrued	25	32
Gas imbalances	17	19
Other	137	161
Total current liabilities	391	780
Other Liabilities:
Accumulated deferred income taxes, net	3	4
Regulatory liabilities	24	24
Other	77	80
Total other liabilities	104	108
Long-Term Debt	4,270	3,969
Commitments and Contingencies (Note 14)
Partners’ Equity:
Series A Preferred Units (14,520,000 issued and outstanding at March 31, 2020 and December 31, 2019)	362	362
Common units (435,443,494 issued and outstanding at March 31, 2020 and 435,201,365 issued and outstanding at December 31, 2019, respectively)	6,972	7,013
Accumulated other comprehensive loss	(9)	(3)
Noncontrolling interest	27	37
Total Partners’ Equity	7,352	7,409
Total Liabilities and Partners’ Equity	$ 12,117	$ 12,266

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - shares	Mar. 31, 2020	Dec. 31, 2019
Common Units
Common units issued	435,443,494	435,201,365
Common units outstanding	435,443,494	435,201,365
Series A Preferred Units
Preferred units issued	14,520,000	14,520,000
Preferred units outstanding	14,520,000	14,520,000

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash Flows from Operating Activities:
Net income	$ 105	$ 123
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	104	105
Deferred income taxes	0	(1)
Impairments	28	0
Loss on sale/retirement of assets	1	1
Equity in earnings of equity method affiliate	(6)	(3)
Return on investment in equity method affiliate	6	3
Equity-based compensation	4	4
Changes in other assets and liabilities:
Accounts receivable, net	52	27
Accounts receivable—affiliated companies	8	2
Inventory	3	(1)
Gas imbalance assets	(1)	7
Other current assets	(6)	10
Other assets	1	5
Accounts payable	(59)	(55)
Accounts payable—affiliated companies	1	0
Gas imbalance liabilities	(2)	(7)
Other current liabilities	(35)	4
Other liabilities	(4)	(9)
Net cash provided by operating activities	200	215
Cash Flows from Investing Activities:
Capital expenditures	(54)	(143)
Return of investment in equity method affiliate	4	9
Other, net	2	(10)
Net cash used in investing activities	(48)	(144)
Cash Flows from Financing Activities:
(Decrease) increase in short-term debt	(45)	147
Proceeds from long-term debt, net of issuance costs	0	200
Repayments of long-term debt	250	0
Proceeds from Lines of Credit	340	0
Repayment of Revolving Credit Facility	(40)	(250)
Distributions to common unitholders	144	138
Distributions to preferred unitholders	(9)	(9)
Distributions to non-controlling interests	(3)	(1)
Cash paid for employee equity-based compensation	(1)	(23)
Net cash used in financing activities	(152)	(74)
Net Decrease in Cash, Cash Equivalents and Restricted Cash	0	(3)
Cash, Cash Equivalents and Restricted Cash at Beginning of Period	4	22
Cash, Cash Equivalents and Restricted Cash at End of Period	$ 4	$ 19

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Partners' Equity (Unaudited) - USD ($) shares in Millions, $ in Millions	Total	Noncontrolling Interest	Series A Preferred UnitsPreferred Units	Common UnitsPartners' Capital	AOCI Attributable to Parent	Cumulative Effect, Period of Adoption, Adjustment	Cumulative Effect, Period of Adoption, AdjustmentCommon UnitsPartners' Capital
Balance, beginning of period at Dec. 31, 2018	$ 7,618	$ 38	$ 362	$ 7,218	$ 0
Balance, beginning of period, units at Dec. 31, 2018			15	433
Changes in Partners' Capital
Net Income	123	1	$ 9	$ 113
Other comprehensive loss	0				0
Distributions	(148)	(1)	(9)	(138)
Equity-based compensation, net of units for employee taxes	(10)			$ (10)
Equity-based compensation, net of units for employee taxes, units				2
Balance, end of period at Mar. 31, 2019	7,583	38	$ 362	$ 7,183	0
Balance, end of period, units at Mar. 31, 2019			15	435
Balance, beginning of period at Dec. 31, 2019	7,409	37	$ 362	$ 7,013	(3)
Balance, beginning of period, units at Dec. 31, 2019			15	435
Changes in Partners' Capital
Net Income	105	(7)	$ 9	$ 103
Other comprehensive loss	(6)				(6)
Distributions	(156)	(3)	(9)	(144)
Equity-based compensation, net of units for employee taxes	3			$ 3
Equity-based compensation, net of units for employee taxes, units				0
Balance, end of period at Mar. 31, 2020	$ 7,352	$ 27	$ 362	$ 6,972	$ (9)
Balance, end of period, units at Mar. 31, 2020			15	435
Changes in Partners' Capital
Impact of adoption of financial instruments-credit losses						$ (3)
Impact of adoption of financial instruments-credit losses \| Accounting Standards Update 2016-13 [Member]						$ (3)	$ (3)

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
Summary of Significant Accounting Policies	Mar. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Organization Enable Midstream Partners, LP is a Delaware limited partnership whose assets and operations are organized into two reportable segments: (i) gathering and processing and (ii) transportation and storage. The gathering and processing segment primarily provides natural gas and crude oil gathering and natural gas processing services to our producer customers. The transportation and storage segment provides interstate and intrastate natural gas pipeline transportation and storage services primarily to our producer, power plant, LDC and industrial end-user customers. The Partnership’s natural gas gathering and processing assets are primarily located in Oklahoma, Texas, Arkansas and Louisiana and serve natural gas production in the Anadarko, Arkoma and Ark-La-Tex Basins. Crude oil gathering assets are located in Oklahoma and serve crude oil production in the SCOOP and STACK plays of the Anadarko Basin and in North Dakota and serve crude oil production in the Bakken Shale formation of the Williston Basin. The Partnership’s natural gas transportation and storage assets consist primarily of an interstate pipeline system extending from western Oklahoma and the Texas Panhandle to Louisiana, an interstate pipeline system extending from Louisiana to Illinois, an intrastate pipeline system in Oklahoma, and our investment in SESH, a pipeline extending from Louisiana to Alabama. CenterPoint Energy and OGE Energy each have 50% of the management interests in Enable GP. Enable GP is the general partner of the Partnership and has no other operating activities. Enable GP is governed by a board made up of two representatives designated by each of CenterPoint Energy and OGE Energy, along with the Partnership’s Chief Executive Officer and three independent board members CenterPoint Energy and OGE Energy mutually agreed to appoint. CenterPoint Energy and OGE Energy also own a 40% and 60% interest, respectively, in the incentive distribution rights held by Enable GP. As of March 31, 2020 , CenterPoint Energy held approximately 53.7% or 233,856,623 of the Partnership’s common units, and OGE Energy held approximately 25.5% or 110,982,805 of the Partnership’s common units. Additionally, CenterPoint Energy holds 14,520,000 Series A Preferred Units. The limited partner interests of the Partnership have limited voting rights on matters affecting the business. As such, limited partners do not have rights to elect the Partnership’s general partner on an annual or continuing basis and may not remove Enable GP, its current general partner, without at least a 75% vote by all unitholders, including all units held by the Partnership’s limited partners, and Enable GP and its affiliates, voting together as a single class. As of March 31, 2020 , the Partnership owned a 50% interest in SESH. See Note 8 for further discussion of SESH. For the three months ended March 31, 2020 , the Partnership held a 50% ownership in Atoka and consolidated Atoka in its Condensed Consolidated Financial Statements as EOIT acted as the managing member of Atoka and had control over the operations of Atoka. In addition, the Partnership held a 60% interest in ESCP, which is consolidated in its Condensed Consolidated Financial Statements as EOCS acted as the managing member of ESCP and had control over the operations of ESCP. Basis of Presentation The accompanying condensed consolidated financial statements and related notes of the Partnership have been prepared pursuant to the rules and regulations of the SEC and GAAP. Pursuant to such rules and regulations, certain disclosures normally included in financial statements prepared in accordance with GAAP have been omitted. The accompanying condensed consolidated financial statements and related notes should be read in conjunction with the consolidated financial statements and related notes included in our Annual Report. The condensed consolidated financial statements and the related notes reflect all normal recurring adjustments that are, in the opinion of management, necessary to present fairly the financial position and results of operations for the respective periods. Amounts reported in the Partnership’s Condensed Consolidated Statements of Income are not necessarily indicative of amounts expected for a full-year period due to the effects of, among other things, (a) seasonal fluctuations in demand for energy and energy services, (b) changes in energy commodity prices, (c) timing of maintenance and other expenditures, (d) acquisitions and dispositions of businesses, assets and other interests, and (e) the impact of the ongoing spread and economic effects of COVID-19 and the recent actions of Saudi Arabia and Russia which have resulted in a substantial decrease in natural gas, NGLs and crude oil prices. For a description of the Partnership’s reportable segments, see Note 16 . Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Depreciation Expense On March 26, 2020, FERC issued an order approving MRT’s 2018 Rate Case and 2019 Rate Case settlements. As a result of the settlements, the new depreciation rates for MRT have been applied in accordance with the order. The new depreciation rates did not result in a material change in depreciation expense or results of operations. Accounts Receivable and Allowance for Doubtful Accounts The Partnership adopted ASU No. 2016-13, “Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments” on January 1, 2020. Upon adoption, the Partnership recognized a $3 million cumulative adjustment to Partners’ Equity and a corresponding adjustment to Allowance for doubtful accounts. Accounts receivable are recorded at the invoiced amount and do not typically bear interest. The determination of the allowance for doubtful accounts requires management to make estimates and judgments regarding our customers’ ability to pay. The allowance for doubtful accounts is determined based primarily upon the historical loss-rate method established for various pools of accounts receivables with similar levels of credit risk. The historical loss-rates are then adjusted, as necessary, based on current conditions and forecasted information that could result in future uncollectable amounts. On an ongoing basis, we evaluate our customers’ financial strength and liquidity based on aging of accounts receivable, payment history, and review of other relevant information, including ratings agency credit ratings and alerts, publicly available reports and news releases, and bank and trade references. It is the policy of management to review the outstanding accounts receivable and other receivable balances within other assets at least quarterly, giving consideration to credit losses, the aging of receivables, specific customer circumstances that may impact their ability to pay the amounts due and current and forecasted economic conditions over the assets contractual lives. The following table summarizes the required allowance for doubtful accounts. March 31, 2020 January 1, 2020 (In millions) Accounts receivable $ 2 $ 2 Other assets 3 3 Total Allowance for doubtful accounts $ 5 $ 5 Inventory Natural gas inventory is held, through the transportation and storage segment, to provide operational support for pipeline deliveries and to manage leased intrastate storage capacity. Natural gas liquids inventory is held, through the gathering and processing segment, due to timing differences between the production of certain natural gas liquids and ultimate sale to third parties. Natural gas and natural gas liquids inventory is valued using moving average cost and is subsequently recorded at the lower of cost or net realizable value. The Partnership recorded write-downs to net realizable value related to natural gas and natural gas liquids inventory of $6 million and $1 million during the three months ended March 31, 2020 and 2019 , respectively.

New Accounting Pronouncements

New Accounting Pronouncements	3 Months Ended
New Accounting Pronouncements	Mar. 31, 2020
Accounting Changes and Error Corrections [Abstract]
New Accounting Pronouncements	New Accounting Pronouncements Accounting Standards to be Adopted in Future Periods Reference Rate Reform In March 2020, the FASB issued ASU No. 2020-04, “Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting.” This standard provides optional guidance, for a limited time, to ease the potential burden in accounting for or recognizing the effects of reference rate reform on financial reporting. The standard was effective upon issuance and generally can be applied through December 31, 2022. The Partnership is currently evaluating the impact this ASU will have on our Condensed Consolidated Financial Statements and related disclosures.

Revenue

Revenue	3 Months Ended
Revenue	Mar. 31, 2020
Revenue from Contract with Customer [Abstract]
Revenue	Revenues The following tables disaggregate total revenues by major source from contracts with customers and the gain (loss) on derivative activity for the three months ended March 31, 2020 and 2019 . Three Months Ended March 31, 2020 Gathering and Transportation Eliminations Total (In millions) Revenues: Product sales: Natural gas $ 56 $ 73 $ (60 ) $ 69 Natural gas liquids 172 2 (2 ) 172 Condensate 27 — — 27 Total revenues from natural gas, natural gas liquids, and condensate 255 75 (62 ) 268 Gain on derivative activity 20 — — 20 Total Product sales $ 275 $ 75 $ (62 ) $ 288 Service revenues: Demand revenues $ 39 $ 142 $ — $ 181 Volume-dependent revenues 163 17 (1 ) 179 Total Service revenues $ 202 $ 159 $ (1 ) $ 360 Total Revenues $ 477 $ 234 $ (63 ) $ 648 Three Months Ended March 31, 2019 Gathering and Transportation Eliminations Total (In millions) Revenues: Product sales: Natural gas $ 128 $ 162 $ (141 ) $ 149 Natural gas liquids 270 6 (6 ) 270 Condensate 34 — — 34 Total revenues from natural gas, natural gas liquids, and condensate 432 168 (147 ) 453 Loss on derivative activity (9 ) (1 ) — (10 ) Total Product sales $ 423 $ 167 $ (147 ) $ 443 Service revenues: Demand revenues $ 60 $ 131 $ — $ 191 Volume-dependent revenues 147 18 (4 ) 161 Total Service revenues $ 207 $ 149 $ (4 ) $ 352 Total Revenues $ 630 $ 316 $ (151 ) $ 795 MRT Rate Case Settlements In June 2018, MRT filed a general NGA rate case (the “2018 Rate Case”), and in October 2019, MRT filed a second rate case (the “2019 Rate Case”). MRT began collecting the rates proposed in the 2018 Rate Case, subject to refund, on January 1, 2019. On March 26, 2020, FERC issued an order approving settlements filed in the 2018 Rate Case and the 2019 Rate Case. Upon issuance of the order and approval of the settlement of the MRT rate cases, the Partnership recognized $17 million of revenues from amounts previously held in reserve related to transportation and storage services performed in 2019. As of March 31, 2020 , $21 million is held in reserve to be refunded to customers, which is inclusive of interest and is expected to be paid in May 2020. Accounts Receivable The following table summarizes the components of accounts receivable, net of allowance for doubtful accounts. March 31, December 31, (In millions) Accounts Receivable: Customers $ 176 $ 239 Contract assets (1) 26 18 Non-customers 7 12 Total Accounts Receivable (2) $ 209 $ 269 ____________________ (1) Contract assets reflected in Total Accounts Receivable include accrued minimum volume commitments. Contract assets are primarily attributable to revenues associated with estimated shortfall volumes on certain annual minimum volume commitment arrangements. Total Accounts Receivable does not include $7 million of contracts assets related to firm service transportation contracts with tiered rates, which are reflected in Other Assets. (2) Total Accounts Receivable includes Accounts receivable, net of allowance for doubtful accounts and Accounts receivable—affiliated companies. Contract Liabilities Our contract liabilities primarily consist of prepayments received from customers for which the good or service has not yet been provided in connection with the prepayment. The table below summarizes the change in the contract liabilities. March 31, December 31, Amounts recognized in revenues (In millions) Deferred revenues (1) $ 47 $ 48 $ 19 The table below summarizes the timing of recognition of these contract liabilities as of March 31, 2020 . 2020 2021 2022 2023 2024 and After (In millions) Deferred revenues (1) $ 22 $ 6 $ 6 $ 6 $ 7 ____________________ (1) Deferred revenues includes deferred revenue — affiliated companies. This amount is included in Other current liabilities and Other long-term liabilities. Remaining Performance Obligations Our remaining performance obligations consist primarily of firm arrangements and minimum volume commitment arrangements. Upon completion of the performance obligations associated with these arrangements, customers are invoiced and revenue is recognized as Service revenues in the Condensed Consolidated Statements of Income. The table below summarizes the timing of recognition of the remaining performance obligations as of March 31, 2020 . 2020 2021 2022 2023 2024 and After (In millions) Transportation and Storage $ 343 $ 308 $ 240 $ 225 $ 702 Gathering and Processing 90 121 123 121 313 Total remaining performance obligations $ 433 $ 429 $ 363 $ 346 $ 1,015

Leases

Leases	3 Months Ended
Leases	Mar. 31, 2020
Leases [Abstract]
Leases	Leases As of March 31, 2020 , we have right-of-use assets of $31 million recorded as Other Assets, $7 million of corresponding obligations recorded as Other Current Liabilities and $27 million of corresponding obligations recorded as Other Liabilities on the Partnership’s Condensed Consolidated Balance Sheet. All lease obligations outstanding during the three months ended March 31, 2020 were classified as operating leases, therefore all cash flows are reflected in Cash Flows from Operating Activities. Rental costs associated with field equipment and buildings were $5 million and $1 million during the three months ended March 31, 2020 , respectively, and $7 million and $2 million during the three months ended March 31, 2019 , respectively. As of March 31, 2020 , the weighted average remaining lease term is 6.7 years and the weighted average discount rate is 5.43% . The following table presents the Partnership’s lease cost. Three Months Ended March 31, 2020 Gathering and Transportation Total (In millions) Lease Cost: Operating lease cost $ 2 $ — $ 2 Short-term lease cost 3 — 3 Variable lease cost 1 — 1 Total Lease Cost $ 6 $ — $ 6 Three Months Ended March 31, 2019 Gathering and Transportation Total (In millions) Lease Cost: Operating lease cost $ 2 $ — $ 2 Short-term lease cost 6 1 7 Total Lease Cost $ 8 $ 1 $ 9 Under ASC 842, as of March 31, 2020 , the Partnership has operating lease obligations expiring at various dates. The $4 million difference between undiscounted cash flows for operating leases and our $34 million of lease obligations is due to the impact of the applicable discount rate. Undiscounted cash flows for operating lease liabilities are as follows: Year Ended December 31, 2020 2021 2022 2023 2024 2025 and After Total (In millions) Noncancellable operating leases $ 7 $ 6 $ 5 $ 5 $ 4 $ 11 $ 38

Earnings Per Limited Partner Un

Earnings Per Limited Partner Unit	3 Months Ended
Earnings Per Limited Partner Unit	Mar. 31, 2020
Earnings Per Share [Abstract]
Earnings Per Limited Partner Unit	Earnings Per Limited Partner Unit The following table illustrates the Partnership’s calculation of earnings per unit for common units. The dilutive effect of the unit-based awards discussed in Note 15 was less than $0.01 per unit during the three months ended March 31, 2020 and 2019 . Three Months Ended March 31, 2020 2019 (In millions, except per unit data) Net income $ 105 $ 123 Net (loss) income attributable to noncontrolling interest (7 ) 1 Series A Preferred Unit distributions 9 9 General partner interest in net income — — Net income available to common unitholders $ 103 $ 113 Net income allocable to common units $ 103 $ 113 Dilutive effect of Series A Preferred Unit distributions 9 — Diluted net income allocable to common units $ 112 $ 113 Basic earnings per unit Common units $ 0.24 $ 0.26 Basic weighted average number of common units outstanding (1) 437 435 Dilutive effect of Series A Preferred Units 144 — Diluted weighted average number of common units outstanding 581 435 Diluted earnings per unit Common units $ 0.19 $ 0.26 ____________________ (1) Basic weighted average number of outstanding common units includes approximately two million and one million time-based phantom units for the three months ended March 31, 2020 and 2019 , respectively.

Partners' Equity

Partners' Equity	3 Months Ended
Partners' Equity	Mar. 31, 2020
Equity [Abstract]
Partners' Equity	Partners’ Equity The Partnership Agreement requires that, within 60 days after the end of each quarter, the Partnership distribute all of its available cash (as defined in the Partnership Agreement) to unitholders of record on the applicable record date. The Partnership paid or has authorized payment of the following cash distributions to common unitholders, as applicable, during 2020 and 2019 (in millions, except for per unit amounts): Three Months Ended Record Date Payment Date Per Unit Distribution Total Cash Distribution March 31, 2020 (1) May 19, 2020 May 27, 2020 $ 0.16525 $ 72 December 31, 2019 February 18, 2020 February 25, 2020 0.3305 144 September 30, 2019 November 19, 2019 November 26, 2019 0.3305 144 June 30, 2019 August 20, 2019 August 27, 2019 0.3305 144 March 31, 2019 May 21, 2019 May 29, 2019 0.318 138 _____________________ (1) The Board of Directors declared this $0.16525 per common unit cash distribution on May 5, 2020 , to be paid on May 27, 2020 to common unitholders of record at the close of business on May 19, 2020 . The Partnership paid or has authorized payment of the following cash distributions to holders of the Series A Preferred Units during 2019 and 2020 (in millions, except for per unit amounts): Three Months Ended Record Date Payment Date Per Unit Distribution Total Cash Distribution March 31, 2020 (1) May 5, 2020 May 15, 2020 $ 0.625 $ 9 December 31, 2019 February 7, 2020 February 14, 2020 0.625 9 September 30, 2019 November 5, 2019 November 14, 2019 0.625 9 June 30, 2019 August 2, 2019 August 14, 2019 0.625 9 March 31, 2019 April 29, 2019 May 15, 2019 0.625 9 _____________________ (1) The Board of Directors declared a $0.625 per Series A Preferred Unit cash distribution on May 5, 2020 , to be paid on May 15, 2020 , to Series A Preferred unitholders of record at the close of business on May 5, 2020 . ATM Program On May 12, 2017, the Partnership entered into an ATM Equity Offering Sales Agreement, pursuant to which the Partnership may issue and sell common units having an aggregate offering price of up to $200 million , by sales methods and at prices determined by market conditions and other factors at the time of our offerings. The Partnership has no obligation to sell any common units under the ATM Program and the Partnership may suspend sales under the ATM Program at any time. During the three months ended March 31, 2020 and 2019 , the Partnership did not issue common units under the ATM Program. As of March 31, 2020 , $197 million of common units remained available for issuance through the ATM Program.

Impairment of Long-lived Assets

Impairment of Long-lived Assets and Goodwill	3 Months Ended
Impairment of Long-lived Assets and Goodwill	Mar. 31, 2020
Impairment of Long-lived Assets and Goodwill [Abstract]
Impairment of Long-lived Assets and Goodwill [Text Block]	(7) Impairments of Long-lived Assets and Goodwill Impairment of Long-lived Assets The Partnership periodically evaluates long-lived assets, including property, plant and equipment when events or changes in circumstances indicate that the carrying value of these assets may not be recoverable. The determination of whether an impairment has occurred is based on an estimate of undiscounted cash flows attributable to the assets, as compared to the carrying value of the assets. Due to decreases in natural gas and NGL market prices during 2020 as a result of the ongoing spread and economic effects of the COVID-19 pandemic, together with the recent dispute over crude oil production levels between Russia and members of OPEC led by Saudi Arabia, as of March 31, 2020, management reassessed the carrying value of the Atoka assets, in which the Partnership owns a 50% interest in the consolidated joint venture, which is a component of the gathering and processing segment. Based on forecasted future undiscounted cash flows, management determined that the carrying value of the Atoka assets were not fully recoverable. The Partnership utilized the income approach (generally accepted valuation approach) to estimate the fair value of these assets. The primary inputs are forecasted cash flows and the discount rate. The fair value measurement is based on inputs that are not observable in the market and thus represent Level 3 inputs. Applying a discounted cash flow model to the property, plant and equipment, the Partnership recognized a $16 million impairment, which is included in Impairments on the Condensed Consolidated Statements of Income during the three months ended March 31, 2020 . Impairment of Goodwill In the fourth quarter of 2017, as a result of the acquisition of ETGP, the Partnership recorded $12 million of goodwill associated with the Ark-La-Tex Basin reporting unit, included in the gathering and processing reportable segment. The Partnership tests its goodwill for impairment annually on October 1st, or more frequently if events or changes in circumstances indicate that the carrying value of goodwill may not be recoverable. Goodwill is assessed for impairment by comparing the fair value of the reporting unit with its book value, including goodwill. During 2020, the energy industry was impacted by current and forward commodity price declines due to t he ongoing spread and economic effects of the COVID-19 pandemic, together with the recent dispute over crude oil production levels between Russia and members of OPEC led by Saudi Arabia . Amid such crude oil, NGL and natural gas price declines, producers have been cutting back spending and shifting their focus from emphasizing reserves growth, to increasing net cash flows and reducing outstanding debt, which consequently resulted in a decrease in rig count and in forecasted producer activity in the Ark-La-Tex Basin reporting unit during the first quarter of 2020. At the same time, unit prices and market multiples for midstream companies with gathering and processing operations have dropped to their lowest levels in the last three years. Due to the continuing decrease in forward commodity prices, the reduction in forecasted producer activities, the resulting decrease in our forecasted cash flows and the increase in the weighted average cost of capital, the Partnership determined that the fair value of the goodwill associated with our Ark-La-Tex Basin reporting unit would more likely than not be impaired. As a result, the Partnership performed a quantitative test for our goodwill and determined that the carrying value of the Ark-La-Tex Basin reporting unit exceeded its fair value and that goodwill associated with the Ark-La-Tex Basin was completely impaired in the amount of $12 million . The impairment is included in Impairments on the Condensed Consolidated Statements of Income for the three months ended March 31, 2020. The following table presents the change in carrying amount of goodwill in each of our reportable segments. Gathering and Processing Transportation and Storage Total (In millions) Balance as of December 31, 2019 $ 12 $ — $ 12 Goodwill impairment (12 ) — (12 ) Balance as of March 31, 2020 $ — $ — $ —

Investment in Equity Method Aff

Investment in Equity Method Affiliate	3 Months Ended
Investment in Equity Method Affiliate	Mar. 31, 2020
Equity Method Investments and Joint Ventures [Abstract]
Investment in Equity Method Affiliate	The Partnership uses the equity method of accounting for investments in entities in which it has an ownership interest between 20% and 50% and exercises significant influence. SESH is owned 50% by Enbridge, Inc. and 50% by the Partnership. Pursuant to the terms of the SESH LLC Agreement, if, at any time, CenterPoint Energy has a right to receive less than 50% of our distributions through its interest in the Partnership and its economic interest in Enable GP, or does not have the ability to exercise certain control rights, Enbridge, Inc. may, under certain circumstances, have the right to purchase the Partnership’s interest in SESH at fair market value, subject to certain exceptions. The Partnership shares operations of SESH with Enbridge, Inc. under service agreements. The Partnership is responsible for the field operations of SESH. SESH reimburses each party for actual costs incurred, which are billed based upon a combination of direct charges and allocations. The Partnership billed SESH $6 million and $3 million during the three months ended March 31, 2020 and 2019 , respectively, associated with these service agreements. The Partnership includes equity in earnings of equity method affiliate under the Other Income (Expense) caption in the Condensed Consolidated Statements of Income. The following table presents the amount of Equity in earnings of equity method affiliate recognized and Distributions from equity method affiliate received. Three Months Ended March 31, 2020 2019 (In millions) Equity in Earnings of Equity Method Affiliate $ 6 $ 3 Distributions from Equity Method Affiliate (1) $ 10 $ 12 ___________________ (1) Distributions from equity method affiliate includes a $6 million and $3 million return on investment and a $4 million and $9 million return of investment for the three months ended March 31, 2020 and 2019 , respectively. The following table includes the summarized financial information of SESH. Three Months Ended March 31, 2020 2019 (In millions) Income Statements: Revenues $ 27 $ 27 Operating income $ 16 $ 11 Net income $ 11 $ 7

Debt

Debt	3 Months Ended
Debt	Mar. 31, 2020
Debt Disclosure [Abstract]
Debt	The following table presents the Partnership’s outstanding debt. March 31, 2020 December 31, 2019 Outstanding Principal Discount (1) Total Debt Outstanding Principal Premium (Discount) (1) Total Debt (In millions) Commercial Paper $ 110 $ — $ 110 $ 155 $ — $ 155 Revolving Credit Facility 300 — 300 — — — 2019 Term Loan Agreement 800 — 800 800 — 800 2024 Notes 600 — 600 600 — 600 2027 Notes 700 (2 ) 698 700 (2 ) 698 2028 Notes 800 (5 ) 795 800 (5 ) 795 2029 Notes 550 (1 ) 549 550 (1 ) 549 2044 Notes 550 — 550 550 — 550 EOIT Senior Notes — — — 250 1 251 Total debt $ 4,410 $ (8 ) $ 4,402 $ 4,405 $ (7 ) $ 4,398 Less: Short-term debt (2) 110 155 Less: Current portion of long-term debt (3) — 251 Less: Unamortized debt expense (4) 22 23 Total long-term debt $ 4,270 $ 3,969 ____________________ (1) Unamortized premium (discount) on long-term debt is amortized over the life of the respective debt. (2) Short-term debt includes $110 million and $155 million of outstanding commercial paper as of March 31, 2020 and December 31, 2019 , respectively. (3) As of December 31, 2019 , Current portion of long-term debt included $251 million outstanding balance of the EOIT Senior Notes which were repaid in March 2020. (4) As of March 31, 2020 and December 31, 2019 , there was an additional $4 million of unamortized debt expense related to the Revolving Credit Facility included in Other assets, not included above. Commercial Paper The Partnership has a commercial paper program, pursuant to which the Partnership is authorized to issue up to $1.4 billion of commercial paper. The commercial paper program is supported by our Revolving Credit Facility, and outstanding commercial paper effectively reduces our borrowing capacity thereunder. There were $110 million and $155 million outstanding under our commercial paper program at March 31, 2020 and December 31, 2019 , respectively. The weighted average interest rate for the outstanding commercial paper was 2.29% as of March 31, 2020 . Revolving Credit Facility On April 6, 2018, the Partnership amended and restated its Revolving Credit Facility. As amended and restated, the Revolving Credit Facility is a $1.75 billion , five -year senior unsecured revolving credit facility, which under certain circumstances may be increased from time to time up to an additional $875 million . The Revolving Credit Facility is scheduled to mature on April 6, 2023, subject to an extension option, which could be exercised two times to extend the term of the Revolving Credit Facility, in each case, for an additional one -year term. As of March 31, 2020 , there were $300 million principal advances and $3 million in letters of credit outstanding under the Revolving Credit Facility. The Revolving Credit Facility provides that outstanding borrowings bear interest at the LIBOR and/or an alternate base rate, at the Partnership’s election, plus an applicable margin. The applicable margin is based on the Partnership’s designated credit ratings from S&P, Moody’s and Fitch Ratings. As of March 31, 2020 , the applicable margin for LIBOR-based borrowings under the Revolving Credit Facility was 1.50% based on the Partnership’s credit ratings. In addition, the Revolving Credit Facility requires the Partnership to pay a fee on unused commitments. The commitment fee is based on the Partnership’s credit ratings. As of March 31, 2020 , the commitment fee under the restated Revolving Credit Facility was 0.20% per annum based on the Partnership’s credit ratings. The commitment fee is recorded as interest expense in the Partnership’s Condensed Consolidated Statements of Income. 2019 Term Loan Agreement On January 29, 2019, the Partnership entered into an unsecured term loan agreement with Bank of America, N.A., as administrative agent, and the several lenders thereto. As of March 31, 2020 , there was $800 million outstanding under the 2019 Term Loan Agreement. The 2019 Term Loan Agreement has a scheduled maturity date of January 29, 2022, but contains an option, which may be exercised up to two times, to extend the maturity date for an additional one-year term. The 2019 Term Loan Agreement provides that outstanding borrowings bear interest at the eurodollar rate and/or an alternate base rate, at the Partnership’s election, plus an applicable margin. The applicable margin is based on the Partnership’s credit ratings. The applicable margin shall equal, (1) in the case of interest rates determined by reference to the eurodollar rate, between 0.75% and 1.50% per annum and (2) in the case of interest rates determined by reference to the alternate base rate, between 0% and 0.50% per annum. As of March 31, 2020 , the applicable margin for LIBOR-based advances under the 2019 Term Loan Facility was 1.25% based on the Partnership’s credit ratings. As of March 31, 2020 , the weighted average interest rate of the 2019 Term Loan Agreement was 3.00% . Senior Notes As of March 31, 2020 , the Partnership’s debt included the 2024 Notes, 2027 Notes, 2028 Notes, 2029 Notes and 2044 Notes, which had $8 million of unamortized discount and $22 million of unamortized debt expense at March 31, 2020 , resulting in effective interest rates of 4.01% , 4.57% , 5.20% , 4.31% and 5.08% , respectively, during the three months ended March 31, 2020 . In March 2020, the Partnership’s EOIT Senior Notes matured and were paid using proceeds from the Revolving Credit Facility. As of March 31, 2020 , the Partnership was in compliance with all of its debt agreements, including financial covenants.

Derivative Instruments and Hedg

Derivative Instruments and Hedging Activities	3 Months Ended
Derivative Instruments and Hedging Activities	Mar. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Hedging Activities	Derivative Instruments and Hedging Activities The primary risks managed using derivative instruments are commodity price and interest rate risks. Derivatives Not Designated as Hedging Instruments Derivative instruments not designated as hedging instruments for accounting purposes are utilized to manage the Partnership’s exposure to commodity price risk. For derivative instruments not designated as hedging instruments, the gain or loss on the derivative is recognized currently in earnings. Quantitative Disclosures Related to Derivative Instruments Not Designated as Hedging Instruments The following table presents the Partnership’s derivative instruments that were not designated as hedging instruments for accounting purposes. March 31, 2020 December 31, 2019 Gross Notional Volume Purchases Sales Purchases Sales Natural gas— TBtu (1) Financial fixed futures/swaps 7 20 10 19 Financial basis futures/swaps 7 30 11 30 Financial swaptions (2) — 7 — 2 Physical purchases/sales — 4 — 6 Crude oil (for condensate)— MBbl (3) Financial futures/swaps — 630 — 990 Financial swaptions (2) — 165 — 225 Natural gas liquids— MBbl (4) Financial futures/swaps 2,205 2,085 2,490 2,415 Financial options — 90 — — ____________________ (1) As of March 31, 2020 , 87.9% of the natural gas contracts had durations of one year or less and 12.1% had durations of more than one year and less than two years. As of December 31, 2019 , 86.6% of the natural gas contracts had durations of one year or less and 13.4% had durations of more than one year and less than two years. (2) The notional volume contains a combined derivative instrument consisting of a fixed price swap and a sold option, which gives the counterparties the right, but not the obligation, to increase the notional volume hedged under the fixed price swap until the option expiration date. The notional volume represents the volume prior to option exercise. (3) As of March 31, 2020 , 77.4% of the crude oil (for condensate) contracts had durations of one year or less and 22.6% had durations of more than one year and less than two years. As of December 31, 2019 , 72.8% of the crude oil (for condensate) contracts had durations of one year or less and 27.2% had durations of more than one year and less than two years. (4) As of March 31, 2020 , 82.5% of the natural gas liquids contracts had durations of one year or less and 17.5% had durations of more than one year and less than two years. As of December 31, 2019 , 72.2% of the natural gas liquid contracts had durations of one year or less and 27.8% had durations of more than one year and less than two years. Derivatives Designated as Hedging Instruments Derivative instruments designated as hedging instruments for accounting purposes are utilized in managing the Partnership’s interest rate risk exposures. Quantitative Disclosures Related to Derivative Instruments Designated as Hedging Instruments The following table presents the Partnership’s derivative instruments that were designated as hedging instruments for accounting purposes. March 31, 2020 December 31, 2019 Gross Notional Value (In millions) Interest rate swaps $ 300 $ 300 Balance Sheet Presentation Related to Derivative Instruments The following table presents the fair value of the derivative instruments that are included in the Partnership’s Condensed Consolidated Balance Sheets that were not designated as hedging instruments for accounting purposes. March 31, 2020 December 31, 2019 Fair Value Instrument Balance Sheet Location Assets Liabilities Assets Liabilities (In millions) Natural gas Financial futures/swaps Other Current $ 7 $ 6 $ 7 $ 5 Financial swaptions Other Current 2 1 — — Financial futures/swaps Other — — — 1 Physical purchases/sales Other Current 4 — 5 — Crude oil (for condensate) Financial futures/swaps Other Current 6 8 1 19 Financial swaptions Other Current 4 — — — Financial futures/swaps Other 1 5 — 8 Natural gas liquids Financial futures/swaps Other Current 16 5 25 3 Financial swaptions Other Current 1 — — — Financial futures/swaps Other 6 1 11 2 Total gross commodity derivatives (1) $ 47 $ 26 $ 49 $ 38 _____________________ (1) See Note 11 for a reconciliation of the Partnership’s commodity derivatives fair value to the Partnership’s Condensed Consolidated Balance Sheets as of March 31, 2020 and December 31, 2019 . The following table presents the fair value of the derivative instruments that are included in the Partnership’s Condensed Consolidated Balance Sheets that were designated as hedging instruments for accounting purposes. March 31, 2020 December 31, 2019 Fair Value Instrument Balance Sheet Location Assets Liabilities Assets Liabilities (In millions) Interest rate swaps Other Current $ — $ 5 $ — $ 1 Interest rate swaps Other — 4 — 2 Total gross interest rate derivatives (1) $ — $ 9 $ — $ 3 _____________________ (1) All interest rate derivative instruments that were designated as cash flow hedges are considered Level 2 as of March 31, 2020 and December 31, 2019 . Income Statement Presentation Related to Derivative Instruments The following table presents the effect of derivative instruments on the Partnership’s Condensed Consolidated Statements of Income. Amounts Recognized in Income Three Months Ended March 31, 2020 2019 (In millions) Natural gas Financial futures/swaps gains (losses) $ 4 $ (1 ) Financial swaptions (losses) (1 ) — Physical purchases/sales gains (losses) 1 (1 ) Crude oil (for condensate) Financial futures/swaps gains (losses) 19 (11 ) Financial swaptions gains 4 — Natural gas liquids Financial futures/swaps (losses) gains (7 ) 3 Total $ 20 $ (10 ) For derivatives not designated as hedges in the tables above, amounts recognized in income for the periods ended March 31, 2020 and 2019 , if any, are reported in Product sales. The following table presents the components of gain (loss) on derivative activity in the Partnership’s Condensed Consolidated Statements of Income. Three Months Ended March 31, 2020 2019 (In millions) Change in fair value of commodity derivatives $ 10 $ (12 ) Realized gain on commodity derivatives 10 2 Gain (loss) on commodity derivative activity $ 20 $ (10 ) Credit-Risk Related Contingent Features in Derivative Instruments In the event Moody’s or S&P were to lower the Partnership’s senior unsecured debt rating to a below investment grade rating, the Partnership could be required to provide additional credit assurances to third parties, which could include letters of credit or cash collateral to satisfy its obligation under its financial and physical contracts relating to derivative instruments that are in a net liability position. As of March 31, 2020 , under these obligations, the Partnership has posted no cash collateral related to natural gas swaps and swaptions, crude oil swaps and swaptions and NGL swaps and no additional collateral would be required to be posted by the Partnership in the event of a credit ratings downgrade to a below investment grade rating. In certain situations where the Partnership’s credit rating is lowered by Moody’s or S&P, the Partnership could be subject to an early termination event related to certain derivative instruments, which could result in a cash settlement of the instruments at market values on the date of such early termination.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
Fair Value Measurements	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	Certain assets and liabilities are recorded at fair value in the Condensed Consolidated Balance Sheets and are categorized based upon the level of judgment associated with the inputs used to measure their value. The Partnership determines the appropriate level for each financial asset and liability on a quarterly basis and recognizes transfers between levels at the end of the reporting period. For the three months ended March 31, 2020 , there were no transfers between levels. As of March 31, 2020 , there were no contracts classified as Level 3. Estimated Fair Value of Financial Instruments The fair values of all accounts receivable, notes receivable, accounts payable, commercial paper and other such financial instruments on the Condensed Consolidated Balance Sheets are estimated to be approximately equivalent to their carrying amounts due to their short-term nature and have been excluded from the table below. The following table summarizes the fair value and carrying amount of the Partnership’s financial instruments. March 31, 2020 December 31, 2019 Carrying Amount Fair Value Carrying Amount Fair Value (In millions) Debt Revolving Credit Facility (Level 2) (1) $ 300 $ 300 $ — $ — 2019 Term Loan Agreement (Level 2) 800 800 800 800 2024 Notes (Level 2) 600 333 600 614 2027 Notes (Level 2) 698 340 698 698 2028 Notes (Level 2) 795 398 795 811 2029 Notes (Level 2) 549 253 549 526 2044 Notes (Level 2) 550 236 550 506 EOIT Senior Notes (Level 2) — — 251 252 ____________________ (1) Borrowing capacity is effectively reduced by our borrowings outstanding under the commercial paper program. $110 million and $155 million of commercial paper was outstanding as of March 31, 2020 and December 31, 2019 , respectively. The fair value of the Partnership’s Revolving Credit Facility, 2019 Term Loan Agreement, 2024 Notes, 2027 Notes, 2028 Notes, 2029 Notes, 2044 Notes and EOIT Senior Notes is based on quoted market prices and estimates of current rates available for similar issues with similar maturities and is classified as Level 2 in the fair value hierarchy. Non-Financial Assets and Liabilities Measured at Fair Value on a Nonrecurring Basis Certain assets and liabilities are measured at fair value on a nonrecurring basis; that is, the assets and liabilities are not measured at fair value on an ongoing basis but are subject to fair value adjustments in certain circumstances (e.g., when there is evidence of impairment). As of March 31, 2020 , no material fair value adjustments or fair value measurements were required for these non-financial assets or liabilities, other than those discussed in Note 7 . Based upon review of forecasted undiscounted cash flows as of March 31, 2020 , all of the asset groups were considered recoverable, other than those discussed in Note 7 . Future price declines, throughput declines, contracted capacity declines, cost increases, regulatory or political environment changes and other changes in market conditions, including the ongoing spread and economic effects of COVID-19 and the recent dispute over crude oil production levels between Russia and members of OPEC led by Saudi Arabia, could reduce forecasted undiscounted cash flows. Contracts with Master Netting Arrangements As of March 31, 2020 , the Partnership’s Level 2 interest rate derivatives are recorded as liabilities with no netting adjustments. The following tables summarize the Partnership’s other assets and liabilities that are measured at fair value on a recurring basis. March 31, 2020 Commodity Contracts Gas Imbalances (1) Assets Liabilities Assets (2) Liabilities (3) (In millions) Quoted market prices in active market for identical assets (Level 1) $ 5 $ 18 $ — $ — Significant other observable inputs (Level 2) 42 8 13 10 Total fair value 47 26 13 10 Netting adjustments (26 ) (26 ) — — Total $ 21 $ — $ 13 $ 10 December 31, 2019 Commodity Contracts Gas Imbalances (1) Assets Liabilities Assets (2) Liabilities (3) (In millions) Quoted market prices in active market for identical assets (Level 1) $ 5 $ 31 $ — $ — Significant other observable inputs (Level 2) 44 7 14 11 Total fair value 49 38 14 11 Netting adjustments (37 ) (37 ) — — Total $ 12 $ 1 $ 14 $ 11 ______________________ (1) The Partnership uses the market approach to fair value its gas imbalance assets and liabilities at individual, or where appropriate an average of, current market indices applicable to the Partnership’s operations, not to exceed net realizable value. There were no netting adjustments as of March 31, 2020 and December 31, 2019 . (2) Gas imbalance assets exclude fuel reserves for under retained fuel due from shippers of $23 million and $21 million at March 31, 2020 and December 31, 2019 , respectively, which fuel reserves are based on the value of natural gas at the time the imbalance was created, and which are not subject to revaluation at fair market value. (3) Gas imbalance liabilities exclude fuel reserves for over retained fuel due to shippers of $7 million and $8 million at March 31, 2020 and December 31, 2019 , respectively, which fuel reserves are based on the value of natural gas at the time the imbalance was created, and which are not subject to revaluation at fair market value.

Supplemental Disclosure of Cash

Supplemental Disclosure of Cash Flow Information	3 Months Ended
Supplemental Disclosure of Cash Flow Information	Mar. 31, 2020
Supplemental Cash Flow Information [Abstract]
Supplemental Disclosure of Cash Flow Information	The following table provides information regarding supplemental cash flow information: Three Months Ended March 31, 2020 2019 (In millions) Supplemental Disclosure of Cash Flow Information: Cash Payments: Interest, net of capitalized interest $ 43 $ 32 Non-cash transactions: Accounts payable related to capital expenditures 8 39 Lease liabilities related to (derecognition) recognition of right-of-use assets (4 ) 35 Impact of adoption of financial instruments-credit losses accounting standard (Note 1) (3 ) — The following table reconciles cash and cash equivalents and restricted cash on the Condensed Consolidated Balance Sheets to cash, cash equivalents and restricted cash on the Condensed Consolidated Statements of Cash Flows: March 31, 2020 2019 (In millions) Cash and cash equivalents $ 4 $ 18 Restricted cash — 1 Cash, cash equivalents and restricted cash shown in the Condensed Consolidated Statements of Cash Flows $ 4 $ 19

Related Party Transactions

Related Party Transactions	3 Months Ended
Related Party Transactions	Mar. 31, 2020
Related Party Transactions [Abstract]
Related Party Transactions	MRT provides firm transportation and firm storage services to CenterPoint Energy’s LDCs in Arkansas and Louisiana. As part of the MRT rate case settlements, contracts for these services were extended and are in effect through July 31, 2028 and will remain in effect thereafter unless and until terminated by either party upon twelve months’ prior written notice. The Partnership’s revenues from affiliated companies accounted for 8% and 6% of total revenues during the three months ended March 31, 2020 and 2019 , respectively. The following table presents the amounts of revenues from affiliated companies included in the Partnership’s Condensed Consolidated Statements of Income. Three Months Ended March 31, 2020 2019 (In millions) Gas transportation and storage service revenues — CenterPoint Energy $ 37 $ 33 Natural gas product sales — CenterPoint Energy — 1 Gas transportation and storage service revenues — OGE Energy 9 13 Natural gas product sales — OGE Energy 5 1 Total revenues — affiliated companies $ 51 $ 48 The following table presents the amounts of natural gas purchased from affiliated companies included in the Partnership’s Condensed Consolidated Statements of Income. Three Months Ended March 31, 2020 2019 (In millions) Cost of natural gas purchases — CenterPoint Energy $ 1 $ — Cost of natural gas purchases — OGE Energy 8 6 Total cost of natural gas purchases — affiliated companies $ 9 $ 6 Corporate services and seconded employees The Partnership receives services and support functions from each of CenterPoint Energy and OGE Energy under services agreements for an initial term that ended on April 30, 2016. The services agreements automatically extend year-to-year at the end of the initial term, unless terminated by the Partnership with at least 90 days’ notice prior to the end of any extension. Additionally, the Partnership may terminate the services agreements at any time with 180 days’ notice, if approved by the Board of Enable GP. The Partnership reimburses CenterPoint Energy and OGE Energy for these services up to annual caps, which for 2020 are $0 million and $1 million , respectively. As of March 31, 2020 , the Partnership had certain employees who are participants under OGE Energy’s defined benefit and retiree medical plans, who will remain seconded to the Partnership, subject to certain termination rights of the Partnership and OGE Energy. The Partnership’s reimbursement of OGE Energy for seconded employee costs arising out of OGE Energy’s defined benefit and retiree medical plans is fixed at actual cost subject to an annual cap of $5 million until secondment is terminated. The following table presents the amounts charged to the Partnership by affiliates for seconded employees, included primarily in Operation and maintenance and General and administrative expenses in the Partnership’s Condensed Consolidated Statements of Income. Three Months Ended March 31, 2020 2019 (In millions) Seconded Employee Costs — OGE Energy $ 3 $ 6

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
Commitments and Contingencies	Mar. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	The Partnership is routinely involved in legal, environmental, tax and regulatory proceedings before various courts, regulatory commissions and governmental agencies regarding matters arising in the ordinary course of business. Some of these proceedings may from time to time involve substantial amounts. The Partnership regularly analyzes current information and, as necessary, provides accruals for probable liabilities on the eventual disposition of these matters. The Partnership does not currently expect the disposition of these matters to have a material adverse effect on its financial condition, results of operations or cash flows. On January 1, 2017, the Partnership entered into a 10 -year gathering and processing agreement, which became effective on July 1, 2018, with an affiliate of Energy Transfer Partners, LP for 400 MMcf/d of deliveries to the Godley Plant in Johnson County, Texas. As of March 31, 2020 , the Partnership estimates the remaining associated minimum volume commitment fee to be $187 million . Minimum volume commitment fees are expected to be $15 million for the remainder of 2020, $23 million per year from 2021 through 2027 and $11 million in 2028 . On September 13, 2018, the Partnership executed a precedent agreement for the development of the Gulf Run Pipeline, an interstate natural gas transportation project. On January 30, 2019, a final investment decision was made by Golden Pass LNG, the cornerstone shipper for the LNG facility to be served by the Gulf Run Pipeline project. Subject to approval of the project by FERC, the Partnership will be required to construct a large-diameter pipeline from northern Louisiana to Gulf Coast markets. In addition, the Partnership requested approval to transfer existing EGT transportation infrastructure to the Gulf Run Pipeline. The Company filed applications with FERC to obtain authorization to construct and operate the pipeline on February 28, 2020. Under the precedent agreement, the Partnership estimates the cost to complete the Gulf Run Pipeline project to fulfill its obligations under the precedent agreement would be as much as $500 million . The project is backed by a 20 -year firm transportation service agreement. The Gulf Run Pipeline connects natural gas producing regions in the U.S., including the Haynesville, Marcellus, Utica and Barnett shales and the Mid-Continent region. The project is expected to be placed into service in 2022. On September 23, 2019, the Partnership entered into an agreement to sell its undivided 1/12th interest in the Bistineau Storage Facility in Louisiana for approximately $19 million . On January 27, 2020, FERC approved the sale. The Partnership closed the sale on April 1, 2020.

Equity-Based Compensation

Equity-Based Compensation	3 Months Ended
Equity-Based Compensation	Mar. 31, 2020
Share-based Payment Arrangement [Abstract]
Equity-Based Compensation	The following table summarizes the Partnership’s equity-based compensation expense related to performance units and phantom units for the Partnership’s employees and independent directors. Three Months Ended March 31, 2020 2019 (In millions) Performance units $ 2 $ 3 Phantom units 2 1 Total compensation expense $ 4 $ 4 The following table presents the assumptions related to the performance share units granted in 2020 . 2020 Number of units granted 933,738 Fair value of units granted $ 7.00 Expected distribution yield 12.27 % Expected price volatility 27.70 % Risk-free interest rate 0.85 % Expected life of units (in years) 3 The following table presents the number of phantom units granted and the grant date fair value related to the phantom units granted in 2020 . 2020 Phantom Units granted 941,732 Fair value of phantom units granted $6.48 - $10.13 Units Outstanding A summary of the activity for the Partnership’s performance units and phantom units applicable to the Partnership’s employees at March 31, 2020 and changes during 2020 are shown in the following table. Performance Units Phantom Units Number of Units Weighted Average Grant-Date Fair Value, Per Unit Number of Units Weighted Average Grant-Date Fair Value, Per Unit (In millions, except unit data) Units outstanding at December 31, 2019 1,393,329 $ 19.04 1,392,560 $ 14.65 Granted (1) 933,738 7.00 941,732 8.41 Vested (2) (381,981 ) 19.25 (347,287 ) 16.10 Forfeited (11,621 ) 19.12 (10,611 ) 14.81 Units outstanding at March 31, 2020 1,933,465 $ 13.18 1,976,394 $ 10.55 Aggregate intrinsic value of units outstanding at March 31, 2020 $ 5 $ 5 _____________________ (1) Performance units represents the target number of performance units granted. The actual number of performance units earned, if any, is dependent upon performance and may range from 0% to 200% of the target. (2) Performance units vested as of March 31, 2020 include 376,292 units from the 2017 annual grant, which were approved by the Board of Directors in 2017 and, based on the level of achievement of a performance goal established by the Board of Directors over the performance period of January 1, 2017 through December 31, 2019 , no performance units vested. Unrecognized Compensation Cost The following table summarizes the Partnership’s unrecognized compensation cost for its non-vested performance units and phantom units, and the weighted-average periods over which the compensation cost is expected to be recognized. March 31, 2020 Unrecognized Compensation Cost (In millions) Weighted Average Period for Recognition (In years) Performance Units $ 16 2.18 Phantom Units 13 1.97 Total $ 29 As of March 31, 2020 , there were 4,987,106 units available for issuance under the long-term incentive plan.

Reportable Segments

Reportable Segments	3 Months Ended
	Mar. 31, 2020
Segment Reporting [Abstract]
Reportable Segments	Reportable Segments The Partnership’s determination of reportable segments considers the strategic operating units under which it manages sales, allocates resources and assesses performance of various products and services to customers in differing regulatory environments. The accounting policies of the reportable segments are the same as those described in the summary of significant accounting policies excerpt in the Partnership’s audited 2019 consolidated financial statements included in the Annual Report. The Partnership uses operating income as the measure of profit or loss for its reportable segments. The Partnership’s assets and operations are organized into two reportable segments: (i) gathering and processing, which primarily provides natural gas and crude oil gathering and natural gas processing services to our producer customers, and (ii) transportation and storage, which provides interstate and intrastate natural gas pipeline transportation and storage service primarily to our producer, power plant, LDC and industrial end-user customers. Financial data for reportable segments are as follows: Three Months Ended March 31, 2020 Gathering and Processing Transportation (1) and Storage Eliminations Total (In millions) Product sales $ 275 $ 75 $ (62 ) $ 288 Service revenues 202 159 (1 ) 360 Total Revenues 477 234 (63 ) 648 Cost of natural gas and natural gas liquids (excluding depreciation and amortization shown separately) 211 78 (63 ) 226 Operation and maintenance, General and administrative 81 45 — 126 Depreciation and amortization 74 30 — 104 Impairments 28 — — 28 Taxes other than income tax 11 7 — 18 Operating income $ 72 $ 74 $ — $ 146 Total Assets $ 9,659 $ 5,702 $ (3,244 ) $ 12,117 Capital expenditures $ 34 $ 20 $ — $ 54 Three Months Ended March 31, 2019 Gathering and Processing Transportation (1) and Storage Eliminations Total (In millions) Product sales $ 423 $ 167 $ (147 ) $ 443 Service revenues 207 149 (4 ) 352 Total Revenues 630 316 (151 ) 795 Cost of natural gas and natural gas liquids (excluding depreciation and amortization shown separately) 360 169 (151 ) 378 Operation and maintenance, General and administrative 84 45 — 129 Depreciation and amortization 74 31 — 105 Taxes other than income tax 11 7 — 18 Operating income $ 101 $ 64 $ — $ 165 Total assets as of December 31, 2019 $ 9,739 $ 5,886 $ (3,359 ) $ 12,266 Capital expenditures $ 107 $ 36 $ — $ 143 _____________________ (1) See Note 8 for discussion regarding ownership interests in SESH and related equity earnings included in the transportation and storage segment for the three months ended March 31, 2020 and 2019 .	[1]

[1]	See Note 8 for discussion regarding ownership interests in SESH and related equity earnings included in the transportation and storage segment for the three months ended March 31, 2020 and 2019 .

Subsequent Event

Subsequent Event	3 Months Ended
Subsequent Event	Mar. 31, 2020
Subsequent Events [Abstract]
Subsequent Event	(17) Subsequent Event On April 8, 2020, we experienced pipeline damage to one of our rich gas gathering systems in the Ark-La-Tex Basin of our gathering and processing segment. We have ceased operation of this system and are in process of abandoning it in-place. We expect to recognize a loss on retirement of approximately $20 million during the second quarter of 2020. Other than recognition of the non-cash loss on retirement, we do not anticipate a material impact to our financial position, results of operations or cash flows related to the abandonment of this system.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
Summary of Significant Accounting Policies (Policies)	Mar. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	Organization Enable Midstream Partners, LP is a Delaware limited partnership whose assets and operations are organized into two reportable segments: (i) gathering and processing and (ii) transportation and storage. The gathering and processing segment primarily provides natural gas and crude oil gathering and natural gas processing services to our producer customers. The transportation and storage segment provides interstate and intrastate natural gas pipeline transportation and storage services primarily to our producer, power plant, LDC and industrial end-user customers. The Partnership’s natural gas gathering and processing assets are primarily located in Oklahoma, Texas, Arkansas and Louisiana and serve natural gas production in the Anadarko, Arkoma and Ark-La-Tex Basins. Crude oil gathering assets are located in Oklahoma and serve crude oil production in the SCOOP and STACK plays of the Anadarko Basin and in North Dakota and serve crude oil production in the Bakken Shale formation of the Williston Basin. The Partnership’s natural gas transportation and storage assets consist primarily of an interstate pipeline system extending from western Oklahoma and the Texas Panhandle to Louisiana, an interstate pipeline system extending from Louisiana to Illinois, an intrastate pipeline system in Oklahoma, and our investment in SESH, a pipeline extending from Louisiana to Alabama. CenterPoint Energy and OGE Energy each have 50% of the management interests in Enable GP. Enable GP is the general partner of the Partnership and has no other operating activities. Enable GP is governed by a board made up of two representatives designated by each of CenterPoint Energy and OGE Energy, along with the Partnership’s Chief Executive Officer and three independent board members CenterPoint Energy and OGE Energy mutually agreed to appoint. CenterPoint Energy and OGE Energy also own a 40% and 60% interest, respectively, in the incentive distribution rights held by Enable GP. As of March 31, 2020 , CenterPoint Energy held approximately 53.7% or 233,856,623 of the Partnership’s common units, and OGE Energy held approximately 25.5% or 110,982,805 of the Partnership’s common units. Additionally, CenterPoint Energy holds 14,520,000 Series A Preferred Units. The limited partner interests of the Partnership have limited voting rights on matters affecting the business. As such, limited partners do not have rights to elect the Partnership’s general partner on an annual or continuing basis and may not remove Enable GP, its current general partner, without at least a 75% vote by all unitholders, including all units held by the Partnership’s limited partners, and Enable GP and its affiliates, voting together as a single class. As of March 31, 2020 , the Partnership owned a 50% interest in SESH. See Note 8 for further discussion of SESH. For the three months ended March 31, 2020 , the Partnership held a 50% ownership in Atoka and consolidated Atoka in its Condensed Consolidated Financial Statements as EOIT acted as the managing member of Atoka and had control over the operations of Atoka. In addition, the Partnership held a 60% interest in ESCP, which is consolidated in its Condensed Consolidated Financial Statements as EOCS acted as the managing member of ESCP and had control over the operations of ESCP.
Basis of Presentation	Basis of Presentation The accompanying condensed consolidated financial statements and related notes of the Partnership have been prepared pursuant to the rules and regulations of the SEC and GAAP. Pursuant to such rules and regulations, certain disclosures normally included in financial statements prepared in accordance with GAAP have been omitted. The accompanying condensed consolidated financial statements and related notes should be read in conjunction with the consolidated financial statements and related notes included in our Annual Report. The condensed consolidated financial statements and the related notes reflect all normal recurring adjustments that are, in the opinion of management, necessary to present fairly the financial position and results of operations for the respective periods. Amounts reported in the Partnership’s Condensed Consolidated Statements of Income are not necessarily indicative of amounts expected for a full-year period due to the effects of, among other things, (a) seasonal fluctuations in demand for energy and energy services, (b) changes in energy commodity prices, (c) timing of maintenance and other expenditures, (d) acquisitions and dispositions of businesses, assets and other interests, and (e) the impact of the ongoing spread and economic effects of COVID-19 and the recent actions of Saudi Arabia and Russia which have resulted in a substantial decrease in natural gas, NGLs and crude oil prices.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
Depreciation Expense	Depreciation Expense On March 26, 2020, FERC issued an order approving MRT’s 2018 Rate Case and 2019 Rate Case settlements. As a result of the settlements, the new depreciation rates for MRT have been applied in accordance with the order. The new depreciation rates did not result in a material change in depreciation expense or results of operations.
Accounts Receivable and Allowance for Doubtful Accounts	Accounts Receivable and Allowance for Doubtful Accounts The Partnership adopted ASU No. 2016-13, “Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments” on January 1, 2020. Upon adoption, the Partnership recognized a $3 million cumulative adjustment to Partners’ Equity and a corresponding adjustment to Allowance for doubtful accounts.
Inventory	Inventory
New Accounting Pronouncements	New Accounting Pronouncements Accounting Standards to be Adopted in Future Periods Reference Rate Reform In March 2020, the FASB issued ASU No. 2020-04, “Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting.” This standard provides optional guidance, for a limited time, to ease the potential burden in accounting for or recognizing the effects of reference rate reform on financial reporting. The standard was effective upon issuance and generally can be applied through December 31, 2022. The Partnership is currently evaluating the impact this ASU will have on our Condensed Consolidated Financial Statements and related disclosures.
Derivatives Instruments and Hedging Activities	The primary risks managed using derivative instruments are commodity price and interest rate risks. Derivatives Not Designated as Hedging Instruments Derivative instruments not designated as hedging instruments for accounting purposes are utilized to manage the Partnership’s exposure to commodity price risk. For derivative instruments not designated as hedging instruments, the gain or loss on the derivative is recognized currently in earnings. Quantitative Disclosures Related to Derivative Instruments Not Designated as Hedging Instruments
Fair Value Measurements	Certain assets and liabilities are recorded at fair value in the Condensed Consolidated Balance Sheets and are categorized based upon the level of judgment associated with the inputs used to measure their value. The Partnership determines the appropriate level for each financial asset and liability on a quarterly basis and recognizes transfers between levels at the end of the reporting period. For the three months ended March 31, 2020 , there were no transfers between levels. As of March 31, 2020 , there were no contracts classified as Level 3.
Contracts with Master Netting Arrangements	Contracts with Master Netting Arrangements
Reportable Segments	The Partnership’s determination of reportable segments considers the strategic operating units under which it manages sales, allocates resources and assesses performance of various products and services to customers in differing regulatory environments. The accounting policies of the reportable segments are the same as those described in the summary of significant accounting policies excerpt in the Partnership’s audited 2019 consolidated financial statements included in the Annual Report. The Partnership uses operating income as the measure of profit or loss for its reportable segments. The Partnership’s assets and operations are organized into two reportable segments: (i) gathering and processing, which primarily provides natural gas and crude oil gathering and natural gas processing services to our producer customers, and (ii) transportation and storage, which provides interstate and intrastate natural gas pipeline transportation and storage service primarily to our producer, power plant, LDC and industrial end-user customers.

Revenue (Tables)

Revenue (Tables)	3 Months Ended
Revenue (Tables)	Mar. 31, 2020
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The following tables disaggregate total revenues by major source from contracts with customers and the gain (loss) on derivative activity for the three months ended March 31, 2020 and 2019 . Three Months Ended March 31, 2020 Gathering and Transportation Eliminations Total (In millions) Revenues: Product sales: Natural gas $ 56 $ 73 $ (60 ) $ 69 Natural gas liquids 172 2 (2 ) 172 Condensate 27 — — 27 Total revenues from natural gas, natural gas liquids, and condensate 255 75 (62 ) 268 Gain on derivative activity 20 — — 20 Total Product sales $ 275 $ 75 $ (62 ) $ 288 Service revenues: Demand revenues $ 39 $ 142 $ — $ 181 Volume-dependent revenues 163 17 (1 ) 179 Total Service revenues $ 202 $ 159 $ (1 ) $ 360 Total Revenues $ 477 $ 234 $ (63 ) $ 648 Three Months Ended March 31, 2019 Gathering and Transportation Eliminations Total (In millions) Revenues: Product sales: Natural gas $ 128 $ 162 $ (141 ) $ 149 Natural gas liquids 270 6 (6 ) 270 Condensate 34 — — 34 Total revenues from natural gas, natural gas liquids, and condensate 432 168 (147 ) 453 Loss on derivative activity (9 ) (1 ) — (10 ) Total Product sales $ 423 $ 167 $ (147 ) $ 443 Service revenues: Demand revenues $ 60 $ 131 $ — $ 191 Volume-dependent revenues 147 18 (4 ) 161 Total Service revenues $ 207 $ 149 $ (4 ) $ 352 Total Revenues $ 630 $ 316 $ (151 ) $ 795
Schedule of Accounts Receivable	The following table summarizes the components of accounts receivable, net of allowance for doubtful accounts. March 31, December 31, (In millions) Accounts Receivable: Customers $ 176 $ 239 Contract assets (1) 26 18 Non-customers 7 12 Total Accounts Receivable (2) $ 209 $ 269 ____________________ (1) Contract assets reflected in Total Accounts Receivable include accrued minimum volume commitments. Contract assets are primarily attributable to revenues associated with estimated shortfall volumes on certain annual minimum volume commitment arrangements. Total Accounts Receivable does not include $7 million of contracts assets related to firm service transportation contracts with tiered rates, which are reflected in Other Assets. (2) Total Accounts Receivable includes Accounts receivable, net of allowance for doubtful accounts and Accounts receivable—affiliated companies.
Summary of Timing Recognition of Contract Liabilities	The table below summarizes the change in the contract liabilities. March 31, December 31, Amounts recognized in revenues (In millions) Deferred revenues (1) $ 47 $ 48 $ 19 The table below summarizes the timing of recognition of these contract liabilities as of March 31, 2020 . 2020 2021 2022 2023 2024 and After (In millions) Deferred revenues (1) $ 22 $ 6 $ 6 $ 6 $ 7
Summary of Timing Recognition of Remaining Performance Obligations	The table below summarizes the timing of recognition of the remaining performance obligations as of March 31, 2020 . 2020 2021 2022 2023 2024 and After (In millions) Transportation and Storage $ 343 $ 308 $ 240 $ 225 $ 702 Gathering and Processing 90 121 123 121 313 Total remaining performance obligations $ 433 $ 429 $ 363 $ 346 $ 1,015
Schedule of New Accounting Pronouncements and Changes in Accounting Principles	The table below summarizes the change in the contract liabilities. March 31, December 31, Amounts recognized in revenues (In millions) Deferred revenues (1) $ 47 $ 48 $ 19

Leases (Tables)

Leases (Tables)	3 Months Ended
Leases (Tables)	Mar. 31, 2020
Leases [Abstract]
Summary of Lease Expense	The following table presents the Partnership’s lease cost. Three Months Ended March 31, 2020 Gathering and Transportation Total (In millions) Lease Cost: Operating lease cost $ 2 $ — $ 2 Short-term lease cost 3 — 3 Variable lease cost 1 — 1 Total Lease Cost $ 6 $ — $ 6 Three Months Ended March 31, 2019 Gathering and Transportation Total (In millions) Lease Cost: Operating lease cost $ 2 $ — $ 2 Short-term lease cost 6 1 7 Total Lease Cost $ 8 $ 1 $ 9
Schedule of Operating Lease Obligations Expiration	Undiscounted cash flows for operating lease liabilities are as follows: Year Ended December 31, 2020 2021 2022 2023 2024 2025 and After Total (In millions) Noncancellable operating leases $ 7 $ 6 $ 5 $ 5 $ 4 $ 11 $ 38

Earnings Per Limited Partner _2

Earnings Per Limited Partner Unit (Tables)	3 Months Ended
Earnings Per Limited Partner Unit (Tables)	Mar. 31, 2020
Earnings Per Share [Abstract]
Schedule Of Earnings Per Unit For Common Units	The following table illustrates the Partnership’s calculation of earnings per unit for common units. The dilutive effect of the unit-based awards discussed in Note 15 was less than $0.01 per unit during the three months ended March 31, 2020 and 2019 . Three Months Ended March 31, 2020 2019 (In millions, except per unit data) Net income $ 105 $ 123 Net (loss) income attributable to noncontrolling interest (7 ) 1 Series A Preferred Unit distributions 9 9 General partner interest in net income — — Net income available to common unitholders $ 103 $ 113 Net income allocable to common units $ 103 $ 113 Dilutive effect of Series A Preferred Unit distributions 9 — Diluted net income allocable to common units $ 112 $ 113 Basic earnings per unit Common units $ 0.24 $ 0.26 Basic weighted average number of common units outstanding (1) 437 435 Dilutive effect of Series A Preferred Units 144 — Diluted weighted average number of common units outstanding 581 435 Diluted earnings per unit Common units $ 0.19 $ 0.26 ____________________ (1) Basic weighted average number of outstanding common units includes approximately two million and one million time-based phantom units for the three months ended March 31, 2020 and 2019 , respectively.

Partners' Equity (Tables)

Partners' Equity (Tables)	3 Months Ended
Partners' Equity (Tables)	Mar. 31, 2020
Equity [Abstract]
Schedule of Equity Transactions with Limited Partner	The Partnership paid or has authorized payment of the following cash distributions to common unitholders, as applicable, during 2020 and 2019 (in millions, except for per unit amounts): Three Months Ended Record Date Payment Date Per Unit Distribution Total Cash Distribution March 31, 2020 (1) May 19, 2020 May 27, 2020 $ 0.16525 $ 72 December 31, 2019 February 18, 2020 February 25, 2020 0.3305 144 September 30, 2019 November 19, 2019 November 26, 2019 0.3305 144 June 30, 2019 August 20, 2019 August 27, 2019 0.3305 144 March 31, 2019 May 21, 2019 May 29, 2019 0.318 138 _____________________ (1) The Board of Directors declared this $0.16525 per common unit cash distribution on May 5, 2020 , to be paid on May 27, 2020 to common unitholders of record at the close of business on May 19, 2020
Schedule of Cash Distributions to Series A Preferred Unitholders	The Partnership paid or has authorized payment of the following cash distributions to holders of the Series A Preferred Units during 2019 and 2020 (in millions, except for per unit amounts): Three Months Ended Record Date Payment Date Per Unit Distribution Total Cash Distribution March 31, 2020 (1) May 5, 2020 May 15, 2020 $ 0.625 $ 9 December 31, 2019 February 7, 2020 February 14, 2020 0.625 9 September 30, 2019 November 5, 2019 November 14, 2019 0.625 9 June 30, 2019 August 2, 2019 August 14, 2019 0.625 9 March 31, 2019 April 29, 2019 May 15, 2019 0.625 9 _____________________ (1) The Board of Directors declared a $0.625 per Series A Preferred Unit cash distribution on May 5, 2020 , to be paid on May 15, 2020 , to Series A Preferred unitholders of record at the close of business on May 5, 2020 .

Impairment of Long-lived Asse_2

Impairment of Long-lived Assets and Goodwill (Tables)	3 Months Ended
Impairment of Long-lived Assets and Goodwill (Tables)	Mar. 31, 2020
Impairment of Long-lived Assets and Goodwill [Abstract]
Schedule of Goodwill [Table Text Block]	The following table presents the change in carrying amount of goodwill in each of our reportable segments. Gathering and Processing Transportation and Storage Total (In millions) Balance as of December 31, 2019 $ 12 $ — $ 12 Goodwill impairment (12 ) — (12 ) Balance as of March 31, 2020 $ — $ — $ —

Investment in Equity Method A_2

Investment in Equity Method Affiliate (Tables)	3 Months Ended
Investment in Equity Method Affiliate (Tables)	Mar. 31, 2020
Equity Method Investments and Joint Ventures [Abstract]
Schedule of Investments Detail	The following table presents the amount of Equity in earnings of equity method affiliate recognized and Distributions from equity method affiliate received. Three Months Ended March 31, 2020 2019 (In millions) Equity in Earnings of Equity Method Affiliate $ 6 $ 3 Distributions from Equity Method Affiliate (1) $ 10 $ 12 ___________________ (1) Distributions from equity method affiliate includes a $6 million and $3 million return on investment and a $4 million and $9 million return of investment for the three months ended March 31, 2020 and 2019 , respectively. The following table includes the summarized financial information of SESH. Three Months Ended March 31, 2020 2019 (In millions) Income Statements: Revenues $ 27 $ 27 Operating income $ 16 $ 11 Net income $ 11 $ 7

Debt (Tables)

Debt (Tables)	3 Months Ended
Debt (Tables)	Mar. 31, 2020
Debt Disclosure [Abstract]
Schedule of Debt	The following table presents the Partnership’s outstanding debt. March 31, 2020 December 31, 2019 Outstanding Principal Discount (1) Total Debt Outstanding Principal Premium (Discount) (1) Total Debt (In millions) Commercial Paper $ 110 $ — $ 110 $ 155 $ — $ 155 Revolving Credit Facility 300 — 300 — — — 2019 Term Loan Agreement 800 — 800 800 — 800 2024 Notes 600 — 600 600 — 600 2027 Notes 700 (2 ) 698 700 (2 ) 698 2028 Notes 800 (5 ) 795 800 (5 ) 795 2029 Notes 550 (1 ) 549 550 (1 ) 549 2044 Notes 550 — 550 550 — 550 EOIT Senior Notes — — — 250 1 251 Total debt $ 4,410 $ (8 ) $ 4,402 $ 4,405 $ (7 ) $ 4,398 Less: Short-term debt (2) 110 155 Less: Current portion of long-term debt (3) — 251 Less: Unamortized debt expense (4) 22 23 Total long-term debt $ 4,270 $ 3,969 ____________________ (1) Unamortized premium (discount) on long-term debt is amortized over the life of the respective debt. (2) Short-term debt includes $110 million and $155 million of outstanding commercial paper as of March 31, 2020 and December 31, 2019 , respectively. (3) As of December 31, 2019 , Current portion of long-term debt included $251 million outstanding balance of the EOIT Senior Notes which were repaid in March 2020. (4) As of March 31, 2020 and December 31, 2019 , there was an additional $4 million of unamortized debt expense related to the Revolving Credit Facility included in Other assets, not included above.

Derivative Instruments and He_2

Derivative Instruments and Hedging Activities (Tables)	3 Months Ended
Derivative Instruments and Hedging Activities (Tables)	Mar. 31, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Instruments	The following table presents the fair value of the derivative instruments that are included in the Partnership’s Condensed Consolidated Balance Sheets that were designated as hedging instruments for accounting purposes. March 31, 2020 December 31, 2019 Fair Value Instrument Balance Sheet Location Assets Liabilities Assets Liabilities (In millions) Interest rate swaps Other Current $ — $ 5 $ — $ 1 Interest rate swaps Other — 4 — 2 Total gross interest rate derivatives (1) $ — $ 9 $ — $ 3 _____________________ (1) All interest rate derivative instruments that were designated as cash flow hedges are considered Level 2 as of March 31, 2020 and December 31, 2019 . The following table presents the Partnership’s derivative instruments that were not designated as hedging instruments for accounting purposes. March 31, 2020 December 31, 2019 Gross Notional Volume Purchases Sales Purchases Sales Natural gas— TBtu (1) Financial fixed futures/swaps 7 20 10 19 Financial basis futures/swaps 7 30 11 30 Financial swaptions (2) — 7 — 2 Physical purchases/sales — 4 — 6 Crude oil (for condensate)— MBbl (3) Financial futures/swaps — 630 — 990 Financial swaptions (2) — 165 — 225 Natural gas liquids— MBbl (4) Financial futures/swaps 2,205 2,085 2,490 2,415 Financial options — 90 — — ____________________ (1) As of March 31, 2020 , 87.9% of the natural gas contracts had durations of one year or less and 12.1% had durations of more than one year and less than two years. As of December 31, 2019 , 86.6% of the natural gas contracts had durations of one year or less and 13.4% had durations of more than one year and less than two years. (2) The notional volume contains a combined derivative instrument consisting of a fixed price swap and a sold option, which gives the counterparties the right, but not the obligation, to increase the notional volume hedged under the fixed price swap until the option expiration date. The notional volume represents the volume prior to option exercise. (3) As of March 31, 2020 , 77.4% of the crude oil (for condensate) contracts had durations of one year or less and 22.6% had durations of more than one year and less than two years. As of December 31, 2019 , 72.8% of the crude oil (for condensate) contracts had durations of one year or less and 27.2% had durations of more than one year and less than two years. (4) As of March 31, 2020 , 82.5% of the natural gas liquids contracts had durations of one year or less and 17.5% had durations of more than one year and less than two years. As of December 31, 2019 , 72.2% of the natural gas liquid contracts had durations of one year or less and 27.8% had durations of more than one year and less than two years. The following table presents the Partnership’s derivative instruments that were designated as hedging instruments for accounting purposes. March 31, 2020 December 31, 2019 Gross Notional Value (In millions) Interest rate swaps $ 300 $ 300
Schedule of Derivative Assets at Fair Value	The following table presents the fair value of the derivative instruments that are included in the Partnership’s Condensed Consolidated Balance Sheets that were not designated as hedging instruments for accounting purposes. March 31, 2020 December 31, 2019 Fair Value Instrument Balance Sheet Location Assets Liabilities Assets Liabilities (In millions) Natural gas Financial futures/swaps Other Current $ 7 $ 6 $ 7 $ 5 Financial swaptions Other Current 2 1 — — Financial futures/swaps Other — — — 1 Physical purchases/sales Other Current 4 — 5 — Crude oil (for condensate) Financial futures/swaps Other Current 6 8 1 19 Financial swaptions Other Current 4 — — — Financial futures/swaps Other 1 5 — 8 Natural gas liquids Financial futures/swaps Other Current 16 5 25 3 Financial swaptions Other Current 1 — — — Financial futures/swaps Other 6 1 11 2 Total gross commodity derivatives (1) $ 47 $ 26 $ 49 $ 38 _____________________ (1) See Note 11 for a reconciliation of the Partnership’s commodity derivatives fair value to the Partnership’s Condensed Consolidated Balance Sheets as of March 31, 2020 and December 31, 2019 .
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value	The following table presents the effect of derivative instruments on the Partnership’s Condensed Consolidated Statements of Income. Amounts Recognized in Income Three Months Ended March 31, 2020 2019 (In millions) Natural gas Financial futures/swaps gains (losses) $ 4 $ (1 ) Financial swaptions (losses) (1 ) — Physical purchases/sales gains (losses) 1 (1 ) Crude oil (for condensate) Financial futures/swaps gains (losses) 19 (11 ) Financial swaptions gains 4 — Natural gas liquids Financial futures/swaps (losses) gains (7 ) 3 Total $ 20 $ (10 )
Schedule of Other Derivatives Not Designated as Hedging Instruments, Statements of Financial Performance and Financial Position, Location	The following table presents the components of gain (loss) on derivative activity in the Partnership’s Condensed Consolidated Statements of Income. Three Months Ended March 31, 2020 2019 (In millions) Change in fair value of commodity derivatives $ 10 $ (12 ) Realized gain on commodity derivatives 10 2 Gain (loss) on commodity derivative activity $ 20 $ (10 )

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
Fair Value Measurements (Tables)	Mar. 31, 2020
Fair Value Disclosures [Abstract]
Schedule of Fair Value and Carrying Amount of Financial Instruments	The following table summarizes the fair value and carrying amount of the Partnership’s financial instruments. March 31, 2020 December 31, 2019 Carrying Amount Fair Value Carrying Amount Fair Value (In millions) Debt Revolving Credit Facility (Level 2) (1) $ 300 $ 300 $ — $ — 2019 Term Loan Agreement (Level 2) 800 800 800 800 2024 Notes (Level 2) 600 333 600 614 2027 Notes (Level 2) 698 340 698 698 2028 Notes (Level 2) 795 398 795 811 2029 Notes (Level 2) 549 253 549 526 2044 Notes (Level 2) 550 236 550 506 EOIT Senior Notes (Level 2) — — 251 252 ____________________ (1) Borrowing capacity is effectively reduced by our borrowings outstanding under the commercial paper program. $110 million and $155 million of commercial paper was outstanding as of March 31, 2020 and December 31, 2019 , respectively.
Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis	The following tables summarize the Partnership’s other assets and liabilities that are measured at fair value on a recurring basis. March 31, 2020 Commodity Contracts Gas Imbalances (1) Assets Liabilities Assets (2) Liabilities (3) (In millions) Quoted market prices in active market for identical assets (Level 1) $ 5 $ 18 $ — $ — Significant other observable inputs (Level 2) 42 8 13 10 Total fair value 47 26 13 10 Netting adjustments (26 ) (26 ) — — Total $ 21 $ — $ 13 $ 10 December 31, 2019 Commodity Contracts Gas Imbalances (1) Assets Liabilities Assets (2) Liabilities (3) (In millions) Quoted market prices in active market for identical assets (Level 1) $ 5 $ 31 $ — $ — Significant other observable inputs (Level 2) 44 7 14 11 Total fair value 49 38 14 11 Netting adjustments (37 ) (37 ) — — Total $ 12 $ 1 $ 14 $ 11 ______________________ (1) The Partnership uses the market approach to fair value its gas imbalance assets and liabilities at individual, or where appropriate an average of, current market indices applicable to the Partnership’s operations, not to exceed net realizable value. There were no netting adjustments as of March 31, 2020 and December 31, 2019 . (2) Gas imbalance assets exclude fuel reserves for under retained fuel due from shippers of $23 million and $21 million at March 31, 2020 and December 31, 2019 , respectively, which fuel reserves are based on the value of natural gas at the time the imbalance was created, and which are not subject to revaluation at fair market value. (3) Gas imbalance liabilities exclude fuel reserves for over retained fuel due to shippers of $7 million and $8 million at March 31, 2020 and December 31, 2019 , respectively, which fuel reserves are based on the value of natural gas at the time the imbalance was created, and which are not subject to revaluation at fair market value.

Supplemental Disclosure of Ca_2

Supplemental Disclosure of Cash Flow Information (Tables)	3 Months Ended
Supplemental Disclosure of Cash Flow Information (Tables)	Mar. 31, 2020
Supplemental Cash Flow Information [Abstract]
Schedule of Cash Flow, Supplemental Disclosures	The following table provides information regarding supplemental cash flow information: Three Months Ended March 31, 2020 2019 (In millions) Supplemental Disclosure of Cash Flow Information: Cash Payments: Interest, net of capitalized interest $ 43 $ 32 Non-cash transactions: Accounts payable related to capital expenditures 8 39 Lease liabilities related to (derecognition) recognition of right-of-use assets (4 ) 35 Impact of adoption of financial instruments-credit losses accounting standard (Note 1) (3 ) —
Schedule of Restricted Cash and Cash Equivalents	The following table reconciles cash and cash equivalents and restricted cash on the Condensed Consolidated Balance Sheets to cash, cash equivalents and restricted cash on the Condensed Consolidated Statements of Cash Flows: March 31, 2020 2019 (In millions) Cash and cash equivalents $ 4 $ 18 Restricted cash — 1 Cash, cash equivalents and restricted cash shown in the Condensed Consolidated Statements of Cash Flows $ 4 $ 19
Schedule of Cash and Cash Equivalents	The following table reconciles cash and cash equivalents and restricted cash on the Condensed Consolidated Balance Sheets to cash, cash equivalents and restricted cash on the Condensed Consolidated Statements of Cash Flows: March 31, 2020 2019 (In millions) Cash and cash equivalents $ 4 $ 18 Restricted cash — 1 Cash, cash equivalents and restricted cash shown in the Condensed Consolidated Statements of Cash Flows $ 4 $ 19

Related Party Transactions (Tab

Related Party Transactions (Tables)	3 Months Ended
Related Party Transactions (Tables)	Mar. 31, 2020
Related Party Transactions [Abstract]
Schedule of Revenues from Related Parties	mounts of revenues from affiliated companies included in the Partnership’s Condensed Consolidated Statements of Income. Three Months Ended March 31, 2020 2019 (In millions) Gas transportation and storage service revenues — CenterPoint Energy $ 37 $ 33 Natural gas product sales — CenterPoint Energy — 1 Gas transportation and storage service revenues — OGE Energy 9 13 Natural gas product sales — OGE Energy 5 1 Total revenues — affiliated companies $ 51 $ 48
Schedule of Natural Gas Purchased From Related Parties	mounts of natural gas purchased from affiliated companies included in the Partnership’s Condensed Consolidated Statements of Income. Three Months Ended March 31, 2020 2019 (In millions) Cost of natural gas purchases — CenterPoint Energy $ 1 $ — Cost of natural gas purchases — OGE Energy 8 6 Total cost of natural gas purchases — affiliated companies $ 9 $ 6
Schedule of Amounts Charged to Partnership by Related Parties	mounts charged to the Partnership by affiliates for seconded employees, included primarily in Operation and maintenance and General and administrative expenses in the Partnership’s Condensed Consolidated Statements of Income. Three Months Ended March 31, 2020 2019 (In millions) Seconded Employee Costs — OGE Energy $ 3 $ 6

Equity-Based Compensation (Tabl

Equity-Based Compensation (Tables)	3 Months Ended
Equity-Based Compensation (Tables)	Mar. 31, 2020
Share-based Payment Arrangement [Abstract]
Disclosure of Share-based Compensation Arrangements by Share-based Payment Award	The following table summarizes the Partnership’s equity-based compensation expense related to performance units and phantom units for the Partnership’s employees and independent directors. Three Months Ended March 31, 2020 2019 (In millions) Performance units $ 2 $ 3 Phantom units 2 1 Total compensation expense $ 4 $ 4 The following table presents the assumptions related to the performance share units granted in 2020 . 2020 Number of units granted 933,738 Fair value of units granted $ 7.00 Expected distribution yield 12.27 % Expected price volatility 27.70 % Risk-free interest rate 0.85 % Expected life of units (in years) 3 The following table presents the number of phantom units granted and the grant date fair value related to the phantom units granted in 2020 . 2020 Phantom Units granted 941,732 Fair value of phantom units granted $6.48 - $10.13
Schedule of Share-based Compensation, Activity	A summary of the activity for the Partnership’s performance units and phantom units applicable to the Partnership’s employees at March 31, 2020 and changes during 2020 are shown in the following table. Performance Units Phantom Units Number of Units Weighted Average Grant-Date Fair Value, Per Unit Number of Units Weighted Average Grant-Date Fair Value, Per Unit (In millions, except unit data) Units outstanding at December 31, 2019 1,393,329 $ 19.04 1,392,560 $ 14.65 Granted (1) 933,738 7.00 941,732 8.41 Vested (2) (381,981 ) 19.25 (347,287 ) 16.10 Forfeited (11,621 ) 19.12 (10,611 ) 14.81 Units outstanding at March 31, 2020 1,933,465 $ 13.18 1,976,394 $ 10.55 Aggregate intrinsic value of units outstanding at March 31, 2020 $ 5 $ 5 _____________________ (1) Performance units represents the target number of performance units granted. The actual number of performance units earned, if any, is dependent upon performance and may range from 0% to 200% of the target. (2) Performance units vested as of March 31, 2020 include 376,292 units from the 2017 annual grant, which were approved by the Board of Directors in 2017 and, based on the level of achievement of a performance goal established by the Board of Directors over the performance period of January 1, 2017 through December 31, 2019 , no performance units vested.
Schedule of Unrecognized Compensation Cost, Nonvested Awards	summarizes the Partnership’s unrecognized compensation cost for its non-vested performance units and phantom units, and the weighted-average periods over which the compensation cost is expected to be recognized. March 31, 2020 Unrecognized Compensation Cost (In millions) Weighted Average Period for Recognition (In years) Performance Units $ 16 2.18 Phantom Units 13 1.97 Total $ 29

Reportable Segments (Tables)

Reportable Segments (Tables)	3 Months Ended
	Mar. 31, 2020
Segment Reporting [Abstract]
Schedule of Financial Data for Business Segments and Services	Financial data for reportable segments are as follows: Three Months Ended March 31, 2020 Gathering and Processing Transportation (1) and Storage Eliminations Total (In millions) Product sales $ 275 $ 75 $ (62 ) $ 288 Service revenues 202 159 (1 ) 360 Total Revenues 477 234 (63 ) 648 Cost of natural gas and natural gas liquids (excluding depreciation and amortization shown separately) 211 78 (63 ) 226 Operation and maintenance, General and administrative 81 45 — 126 Depreciation and amortization 74 30 — 104 Impairments 28 — — 28 Taxes other than income tax 11 7 — 18 Operating income $ 72 $ 74 $ — $ 146 Total Assets $ 9,659 $ 5,702 $ (3,244 ) $ 12,117 Capital expenditures $ 34 $ 20 $ — $ 54 Three Months Ended March 31, 2019 Gathering and Processing Transportation (1) and Storage Eliminations Total (In millions) Product sales $ 423 $ 167 $ (147 ) $ 443 Service revenues 207 149 (4 ) 352 Total Revenues 630 316 (151 ) 795 Cost of natural gas and natural gas liquids (excluding depreciation and amortization shown separately) 360 169 (151 ) 378 Operation and maintenance, General and administrative 84 45 — 129 Depreciation and amortization 74 31 — 105 Taxes other than income tax 11 7 — 18 Operating income $ 101 $ 64 $ — $ 165 Total assets as of December 31, 2019 $ 9,739 $ 5,886 $ (3,359 ) $ 12,266 Capital expenditures $ 107 $ 36 $ — $ 143 _____________________ (1) See Note 8 for discussion regarding ownership interests in SESH and related equity earnings included in the transportation and storage segment for the three months ended March 31, 2020 and 2019 .	[1]

[1]	See Note 8 for discussion regarding ownership interests in SESH and related equity earnings included in the transportation and storage segment for the three months ended March 31, 2020 and 2019 .

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)board_membersegmentshares	Mar. 31, 2019USD ($)	Jan. 01, 2020USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Significant Accounting Policies [Line Items]
Partners' Capital, Including Portion Attributable to Noncontrolling Interest	$ 7,352	$ 7,583		$ 7,409	$ 7,618
Number of reportable segments \| segment	2
Number of representatives designated by each of CenterPoint Energy and OGE Energy \| board_member	2
Number of independent board members \| board_member	3
Percentage vote by all unitholders (at least 75%)	75.00%
Accounts receivable	$ 2		$ 2
Other assets	3		3
Total Allowance for doubtful accounts	5		$ 5
Inventory adjustments	$ 6	1
SESH
Significant Accounting Policies [Line Items]
Ownership percentage	50.00%
OGE Energy \| Common Units
Significant Accounting Policies [Line Items]
Units outstanding \| shares	110,982,805
CenterPoint \| Common Units
Significant Accounting Policies [Line Items]
Units outstanding \| shares	233,856,623
Limited Partner \| OGE Energy
Significant Accounting Policies [Line Items]
Percentage share of management rights	50.00%
Percentage share of incentive distribution rights	60.00%
Limited Partner \| CenterPoint
Significant Accounting Policies [Line Items]
Percentage share of management rights	50.00%
Percentage share of incentive distribution rights	40.00%
Limited Partner \| CenterPoint \| Series A 10% Fixed to Floating Non Cumulative Redeemable Perpetual Preferred Units
Significant Accounting Policies [Line Items]
Preferred units issued \| shares	14,520,000
OGE Energy \| Limited Partner
Significant Accounting Policies [Line Items]
Limited partner ownership interest percentage	25.50%
Atoka
Significant Accounting Policies [Line Items]
Ownership interest (as a percentage)	50.00%
ESCP
Significant Accounting Policies [Line Items]
Ownership interest (as a percentage)	60.00%
CenterPoint \| Limited Partner
Significant Accounting Policies [Line Items]
Limited partner ownership interest percentage	53.70%
Limited Partner \| Common Units
Significant Accounting Policies [Line Items]
Partners' Capital, Including Portion Attributable to Noncontrolling Interest	$ 6,972	$ 7,183		$ 7,013	$ 7,218
Cumulative Effect, Period of Adoption, Adjustment
Significant Accounting Policies [Line Items]
Impact of adoption of financial instruments-credit losses	(3)
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment
Significant Accounting Policies [Line Items]
Impact of adoption of financial instruments-credit losses	(3)
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment \| Limited Partner \| Common Units
Significant Accounting Policies [Line Items]
Impact of adoption of financial instruments-credit losses	$ (3)

Revenue - Disaggregation of Rev

Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Disaggregation of Revenue [Line Items]
Total revenues from natural gas, natural gas liquids, and condensate	$ 268	$ 453
Gain (loss) on derivative activity	20	(10)
Total Revenues	648	795
Natural gas
Disaggregation of Revenue [Line Items]
Total revenues from natural gas, natural gas liquids, and condensate	69	149
Natural gas liquids
Disaggregation of Revenue [Line Items]
Total revenues from natural gas, natural gas liquids, and condensate	172	270
Condensate Natural Gas
Disaggregation of Revenue [Line Items]
Total revenues from natural gas, natural gas liquids, and condensate	27	34
Product
Disaggregation of Revenue [Line Items]
Total Revenues	288	443
Demand Service Revenue
Disaggregation of Revenue [Line Items]
Total Revenues	181	191
Volume Dependant Service Revenue
Disaggregation of Revenue [Line Items]
Total Revenues	179	161
Natural Gas, Gathering, Transportation, Marketing and Processing
Disaggregation of Revenue [Line Items]
Total Revenues	360	352
Operating Segments \| Gathering and Processing
Disaggregation of Revenue [Line Items]
Total revenues from natural gas, natural gas liquids, and condensate	255	432
Gain (loss) on derivative activity	20	(9)
Total Revenues	477	630
Operating Segments \| Gathering and Processing \| Natural gas
Disaggregation of Revenue [Line Items]
Total revenues from natural gas, natural gas liquids, and condensate	56	128
Operating Segments \| Gathering and Processing \| Natural gas liquids
Disaggregation of Revenue [Line Items]
Total revenues from natural gas, natural gas liquids, and condensate	172	270
Operating Segments \| Gathering and Processing \| Condensate Natural Gas
Disaggregation of Revenue [Line Items]
Total revenues from natural gas, natural gas liquids, and condensate	27	34
Operating Segments \| Gathering and Processing \| Product
Disaggregation of Revenue [Line Items]
Total Revenues	275	423
Operating Segments \| Gathering and Processing \| Demand Service Revenue
Disaggregation of Revenue [Line Items]
Total Revenues	39	60
Operating Segments \| Gathering and Processing \| Volume Dependant Service Revenue
Disaggregation of Revenue [Line Items]
Total Revenues	163	147
Operating Segments \| Gathering and Processing \| Natural Gas, Gathering, Transportation, Marketing and Processing
Disaggregation of Revenue [Line Items]
Total Revenues	202	207
Operating Segments \| Transportation and Storage
Disaggregation of Revenue [Line Items]
Total revenues from natural gas, natural gas liquids, and condensate	75	168
Gain (loss) on derivative activity	0	(1)
Total Revenues	234	316
Operating Segments \| Transportation and Storage \| Natural gas
Disaggregation of Revenue [Line Items]
Total revenues from natural gas, natural gas liquids, and condensate	73	162
Operating Segments \| Transportation and Storage \| Natural gas liquids
Disaggregation of Revenue [Line Items]
Total revenues from natural gas, natural gas liquids, and condensate	2	6
Operating Segments \| Transportation and Storage \| Condensate Natural Gas
Disaggregation of Revenue [Line Items]
Total revenues from natural gas, natural gas liquids, and condensate	0	0
Operating Segments \| Transportation and Storage \| Product
Disaggregation of Revenue [Line Items]
Total Revenues	75	167
Operating Segments \| Transportation and Storage \| Demand Service Revenue
Disaggregation of Revenue [Line Items]
Total Revenues	142	131
Operating Segments \| Transportation and Storage \| Volume Dependant Service Revenue
Disaggregation of Revenue [Line Items]
Total Revenues	17	18
Operating Segments \| Transportation and Storage \| Natural Gas, Gathering, Transportation, Marketing and Processing
Disaggregation of Revenue [Line Items]
Total Revenues	159	149
Eliminations
Disaggregation of Revenue [Line Items]
Total revenues from natural gas, natural gas liquids, and condensate	(62)	(147)
Gain (loss) on derivative activity	0	0
Total Revenues	(63)	(151)
Eliminations \| Natural gas
Disaggregation of Revenue [Line Items]
Total revenues from natural gas, natural gas liquids, and condensate	(60)	(141)
Eliminations \| Natural gas liquids
Disaggregation of Revenue [Line Items]
Total revenues from natural gas, natural gas liquids, and condensate	(2)	(6)
Eliminations \| Condensate Natural Gas
Disaggregation of Revenue [Line Items]
Total revenues from natural gas, natural gas liquids, and condensate	0	0
Eliminations \| Product
Disaggregation of Revenue [Line Items]
Total Revenues	(62)	(147)
Eliminations \| Demand Service Revenue
Disaggregation of Revenue [Line Items]
Total Revenues	0	0
Eliminations \| Volume Dependant Service Revenue
Disaggregation of Revenue [Line Items]
Total Revenues	(1)	(4)
Eliminations \| Natural Gas, Gathering, Transportation, Marketing and Processing
Disaggregation of Revenue [Line Items]
Total Revenues	$ (1)	$ (4)

Revenue - Narrative (Details)

Revenue - Narrative (Details) $ in Millions	3 Months Ended
Revenue - Narrative (Details) $ in Millions	Mar. 31, 2020USD ($)
Regulatory Liabilities [Line Items]
Revenue recognized related to rate case settlement	$ 17
Revenue Subject to Refund
Regulatory Liabilities [Line Items]
Liability held in reserve to be refunded to customer	$ 21

Revenue - Accounts Receivable (

Revenue - Accounts Receivable (Details) - USD ($) $ in Millions		Mar. 31, 2020	Dec. 31, 2019
Disaggregation of Revenue [Line Items]
Customers		$ 176	$ 239
Contract assets	[1]	26	18
Non-customers		7	12
Total Accounts Receivable	[2]	209	$ 269
Firm Service Transportation [Member]
Disaggregation of Revenue [Line Items]
Contract assets		$ 7

[1]	Contract assets reflected in Total Accounts Receivable include accrued minimum volume commitments. Contract assets are primarily attributable to revenues associated with estimated shortfall volumes on certain annual minimum volume commitment arrangements. Total Accounts Receivable does not include $7 million of contracts assets related to firm service transportation contracts with tiered rates, which are reflected in Other Assets.
[2]	Total Accounts Receivable includes Accounts receivable, net of allowance for doubtful accounts and Accounts receivable—affiliated companies.

Revenue - Summary of Changes in

Revenue - Summary of Changes in Contract Liabilities (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Deferred revenues (1)	$ 47	$ 48
Amounts recognized in revenues	$ 19

Revenue - Summary of Recognitio

Revenue - Summary of Recognition Contract Liabilities (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)
Revenue from Contract with Customer [Abstract]
2020	$ 22
2021	6
2022	6
2023	6
2024 and After	$ 7

Revenue - Summary of Recognit_2

Revenue - Summary of Recognition of Remaining Performance Obligations (Details) $ in Millions	Mar. 31, 2020USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Total remaining performance obligations	$ 433
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01 \| Transportation and Storage
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Total remaining performance obligations	$ 343
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01 \| Gathering and Processing
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Total remaining performance obligations	$ 90
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Total remaining performance obligations	$ 429
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01 \| Transportation and Storage
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Total remaining performance obligations	$ 308
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01 \| Gathering and Processing
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Total remaining performance obligations	$ 121
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Total remaining performance obligations	$ 363
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01 \| Transportation and Storage
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Total remaining performance obligations	$ 240
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01 \| Gathering and Processing
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Total remaining performance obligations	$ 123
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Total remaining performance obligations	$ 346
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01 \| Transportation and Storage
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Total remaining performance obligations	$ 225
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01 \| Gathering and Processing
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	1 year
Total remaining performance obligations	$ 121
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	26 years 5 months
Total remaining performance obligations	$ 1,015
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01 \| Transportation and Storage
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	26 years 5 months
Total remaining performance obligations	$ 702
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01 \| Gathering and Processing
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period	4 years 2 months
Total remaining performance obligations	$ 313

Leases - Narrative (Details)

Leases - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Leases - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2020	Mar. 31, 2019	Jan. 01, 2019
Lessee, Lease, Description [Line Items]
Right-of-use assets	$ 34
Difference between undiscounted cash flows for operating leases	$ 4
Lease liabilities			$ 35
Weighted average lease term (in years)	6 years 8 months 12 days
Weighted average discount rate (as a percentage)	5.43%
Rental costs	$ 6	$ 9
Other Assets
Lessee, Lease, Description [Line Items]
Right-of-use assets	31
Other Current Liabilities
Lessee, Lease, Description [Line Items]
Operating Lease, Liability, Current	7
Other Liabilities
Lessee, Lease, Description [Line Items]
Operating Lease, Liability, Noncurrent	27
Field equipment
Lessee, Lease, Description [Line Items]
Rental costs	5	7
Buildings
Lessee, Lease, Description [Line Items]
Rental costs	$ 1	$ 2
Minimum \| Field equipment
Lessee, Lease, Description [Line Items]
Expected lease term (in years)	3 years
Contractual base terms (in years)	1 year
Minimum \| Buildings
Lessee, Lease, Description [Line Items]
Contractual base terms (in years)	7 years

Leases - Summary of Lease Expen

Leases - Summary of Lease Expense (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Lessee, Lease, Description [Line Items]
Operating lease cost	$ 2	$ 2
Short-term lease cost	3	7
Variable Lease, Cost	1
Total Lease Cost	6	9
Gathering and Processing
Lessee, Lease, Description [Line Items]
Operating lease cost	2	2
Short-term lease cost	3	6
Variable Lease, Cost	1
Total Lease Cost	6	8
Transportation and Storage
Lessee, Lease, Description [Line Items]
Operating lease cost	0	0
Short-term lease cost	0	1
Variable Lease, Cost	0
Total Lease Cost	$ 0	$ 1

Leases - Schedule of Operating

Leases - Schedule of Operating Lease Obligations Expiration (Details) $ in Millions	Mar. 31, 2020USD ($)
Leases [Abstract]
2020	$ 7
2021	6
2022	5
2023	5
2024	4
2025 and After	11
Total	$ 38

Earnings Per Limited Partner _3

Earnings Per Limited Partner Unit (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income		$ 105	$ 123
Net (loss) income attributable to noncontrolling interest		(7)	1
Series A Preferred Unit distributions		9	9
General partner interest in net income		0	0
Net Income Attributable to Common Units (Note 5)		103	$ 113
Phantom units
Basic weighted average number of outstanding
Basic weighted average number of outstanding	[1]		1,000,000
Common Units
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net Income Attributable to Common Units (Note 5)		103	$ 113
Dilutive effect of Series A Preferred Unit distributions		9	0
Diluted net income		$ 112	$ 113
Basic weighted average number of outstanding
Basic weighted average number of outstanding		437	435	[1]
Basic earnings per unit
Basic earnings per unit		$ 0.24	$ 0.26
Dilutive effect of Series A Preferred Units (in units)		144	0
Diluted weighted average number of outstanding units		581	435
Diluted earnings per unit		$ 0.19	$ 0.26
Performance Units and Phantom Units [Member]
Basic earnings per unit
Earnings Per Share, Diluted, Undistributed		$ 0.01	$ 0.01

[1]	Basic weighted average number of outstanding common units includes approximately two million and one million time-based phantom units for the three months ended March 31, 2020 and 2019 , respectively.

Partners' Equity - Schedule of

Partners' Equity - Schedule of Cash Distributions (Details) - USD ($) $ / shares in Units, $ in Millions

May 27, 2020

May 19, 2020

May 15, 2020

May 05, 2020

Feb. 25, 2020

Feb. 18, 2020

Feb. 14, 2020

Feb. 07, 2020

Nov. 26, 2019

Nov. 19, 2019

Nov. 14, 2019

Nov. 05, 2019

Aug. 27, 2019

Aug. 20, 2019

Aug. 14, 2019

Aug. 02, 2019

May 29, 2019

May 21, 2019

May 15, 2019

Apr. 29, 2019

Distribution Made to Limited Partner [Line Items]

Record Date

Feb. 18,
2020

Nov. 19,
2019

Aug. 20,
2019

May 21,
2019

Payment Date

Feb. 25,
2020

Nov. 26,
2019

Aug. 27,
2019

May 29,
2019

Cash distribution declared (in dollars per unit)

$ 0.3305

Distribution made to unitholders

$ 144

Series A 10% Fixed to Floating Non Cumulative Redeemable Perpetual Preferred Units | Preferred Units

Distribution Made to Limited Partner [Line Items]

Record Date

Feb. 7,
2020

Nov. 5,
2019

Aug. 2,
2019

Apr. 29,
2019

Payment Date

Feb. 14,
2020

Nov. 14,
2019

Aug. 14,
2019

May 15,
2019

Cash Distribution

Distribution Made to Limited Partner [Line Items]

Cash distribution declared (in dollars per unit)

$ 0.3305

$ 0.318

Distribution made to unitholders

$ 144

$ 138

Cash Distribution | Series A 10% Fixed to Floating Non Cumulative Redeemable Perpetual Preferred Units | Preferred Units

Distribution Made to Limited Partner [Line Items]

Cash distribution declared (in dollars per unit)

$ 0.625

Distribution made to unitholders

$ 9

Subsequent Event | Cash Distribution | Series A 10% Fixed to Floating Non Cumulative Redeemable Perpetual Preferred Units | Preferred Units

Distribution Made to Limited Partner [Line Items]

Record Date

[1]

May 5,
2020

Payment Date

[1]

May 15,
2020

Cash distribution declared (in dollars per unit)

[1]

$ 0.625

Distribution made to unitholders

[1]

$ 9

Cash distribution (in dollars per unit)

$ 0.625

Forecast | Subsequent Event

Distribution Made to Limited Partner [Line Items]

Record Date

[2]

May 19,
2020

Payment Date

[2]

May 27,
2020

Distribution made to unitholders

[2]

$ 72

Forecast | Subsequent Event | Cash Distribution

Distribution Made to Limited Partner [Line Items]

Cash distribution declared (in dollars per unit)

$ 0.16525

[1]

The Board of Directors declared a $0.625 per Series A Preferred Unit cash distribution on May 5, 2020 , to be paid on May 15, 2020 , to Series A Preferred unitholders of record at the close of business on May 5, 2020 .

[2]

The Board of Directors declared this $0.16525 per common unit cash distribution on May 5, 2020 , to be paid on May 27, 2020 to common unitholders of record at the close of business on May 19, 2020

Partners' Equity - Narrative (D

Partners' Equity - Narrative (Details) - USD ($)	May 12, 2017	Mar. 31, 2020
Distribution Made to Limited Partner [Line Items]
Limited partners' capital account, required quarterly distribution period		60 days
Common units available for issuance through ATM Program		$ 197,000,000
ATM Program
Distribution Made to Limited Partner [Line Items]
Aggregate offering price	$ 200,000,000

Goodwill (Details)

Goodwill (Details) $ in Millions	3 Months Ended
Goodwill (Details) $ in Millions	Mar. 31, 2020USD ($)
Goodwill [Roll Forward]
Goodwill	$ 12
Goodwill impairment	(12)
Goodwill	0
Gathering and Processing
Goodwill [Roll Forward]
Goodwill	12
Goodwill impairment	(12)
Goodwill	0
Transportation and Storage
Goodwill [Roll Forward]
Goodwill	0
Goodwill impairment	0
Goodwill	$ 0

Impairment of Long-Lived Asse_3

Impairment of Long-Lived Assets (Details) - USD ($) $ in Millions	Apr. 08, 2020	Mar. 31, 2020
Atoka
Impaired Long-Lived Assets Held and Used [Line Items]
Ownership interest (as a percentage)		50.00%
Atoka \| Gathering and Processing
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment of Property, Plant and Equipment		$ 16
Subsequent Event \| Gathering and Processing
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment of Property, Plant and Equipment	$ 20

Investment in Equity Method A_3

Investment in Equity Method Affiliate - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Schedule of Equity Method Investments [Line Items]
Amount billed associated with service agreements	$ 648	$ 795
Return on investment in equity method affiliate	6	3
Return of investment in equity method affiliate	$ 4	9
SESH
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.00%
Percentage of distributions through limited partner interest	50.00%
Return on investment in equity method affiliate	$ 6	3
Return of investment in equity method affiliate	4	9
SESH \| Equity Method Investee \| Shared Operations Service Agreements
Schedule of Equity Method Investments [Line Items]
Amount billed associated with service agreements	$ 6	$ 3

Investment in Equity Method A_4

Investment in Equity Method Affiliate - Schedule of Investments (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Equity in Earnings of Equity Method Affiliates:
Equity in earnings of equity method affiliate	$ 6	$ 3
Distributions from Equity Method Affiliates:
Return on investment in equity method affiliate	6	3
Return of investment in equity method affiliate	4	9
Operating income	146	165
Net income	105	123
SESH
Equity in Earnings of Equity Method Affiliates:
Equity in earnings of equity method affiliate	6	3
Distributions from Equity Method Affiliates:
Distributions from equity method affiliate	10	12
Return on investment in equity method affiliate	6	3
Return of investment in equity method affiliate	4	9
Revenues	27	27
Operating income	16	11
Net income	$ 11	$ 7

Debt - Schedule of Outstanding

Debt - Schedule of Outstanding Debt (Details) - USD ($)		Apr. 06, 2018	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Outstanding Principal			$ 4,410,000,000	$ 4,405,000,000
Premium (Discount)			(8,000,000)	(7,000,000)
Total Debt			4,402,000,000	4,398,000,000
Short-term debt			110,000,000	155,000,000
Less: Unamortized debt expense	[1]		(22,000,000)	(23,000,000)
Total long-term debt			4,270,000,000	3,969,000,000
2019 Term Loan Agreement \| 2019 Term Loan Agreement
Debt Instrument [Line Items]
Outstanding Principal			800,000,000	800,000,000
Premium (Discount)			0	0
Total Debt			800,000,000	800,000,000
Senior Notes \| 2019 Notes
Debt Instrument [Line Items]
Less: Current portion of long-term debt	[2]			251,000,000
Senior Notes \| 2024 Notes
Debt Instrument [Line Items]
Outstanding Principal			600,000,000	600,000,000
Premium (Discount)			0	0
Total Debt			$ 600,000,000	600,000,000
Debt Instrument, Interest Rate During Period			4.01%
Senior Notes \| 2027 Notes
Debt Instrument [Line Items]
Outstanding Principal			$ 700,000,000	700,000,000
Premium (Discount)			(2,000,000)	(2,000,000)
Total Debt			$ 698,000,000	698,000,000
Debt Instrument, Interest Rate During Period			4.57%
Senior Notes \| 2028 Notes
Debt Instrument [Line Items]
Outstanding Principal			$ 800,000,000	800,000,000
Premium (Discount)			(5,000,000)	(5,000,000)
Total Debt			$ 795,000,000	795,000,000
Debt Instrument, Interest Rate During Period			5.20%
Senior Notes \| 2029 Notes
Debt Instrument [Line Items]
Outstanding Principal			$ 550,000,000	550,000,000
Premium (Discount)			(1,000,000)	(1,000,000)
Total Debt			$ 549,000,000	549,000,000
Debt Instrument, Interest Rate During Period			4.31%
Senior Notes \| 2044 Notes
Debt Instrument [Line Items]
Outstanding Principal			$ 550,000,000	550,000,000
Premium (Discount)			0	0
Total Debt			$ 550,000,000	550,000,000
Debt Instrument, Interest Rate During Period			5.08%
Senior Notes \| EOIT Senior Notes
Debt Instrument [Line Items]
Less: Current portion of long-term debt	[2]		$ 0
Senior Notes \| EOIT Senior Notes \| EOIT
Debt Instrument [Line Items]
Outstanding Principal			0	250,000,000
Premium (Discount)			0	1,000,000
Total Debt			0	251,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Debt Instrument, Term of Extension Period		1 year
Outstanding Principal			300,000,000	0
Premium (Discount)			0	0
Total Debt			300,000,000	0
Unamortized debt expense related to Revolving Credit Facility			4,000,000	4,000,000
Commercial Paper
Debt Instrument [Line Items]
Premium (Discount)			0	0
Short-term debt	[3]		$ 110,000,000	$ 155,000,000

[1]	As of March 31, 2020 and December 31, 2019 , there was an additional $4 million of unamortized debt expense related to the Revolving Credit Facility included in Other assets, not included above.
[2]	As of December 31, 2019 , Current portion of long-term debt included $251 million outstanding balance of the EOIT Senior Notes which were repaid in March 2020.
[3]	Short-term debt includes $110 million and $155 million of outstanding commercial paper as of March 31, 2020 and December 31, 2019 , respectively.

Debt - Narrative (Details)

Debt - Narrative (Details) - USD ($)		Apr. 06, 2018	Mar. 31, 2020	Dec. 31, 2019	Jan. 29, 2019
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 1,750,000,000
Increase in maximum borrowing capacity		$ 875,000,000
Number of times option maybe exercised to extend term of Term Loan Facility		2
Commercial paper, authorized			$ 1,400,000,000
Commercial paper outstanding			110,000,000	$ 155,000,000
Premium (Discount)			(8,000,000)	(7,000,000)
Outstanding Principal			$ 4,410,000,000	4,405,000,000
2019 Term Loan Agreement
Debt Instrument [Line Items]
Weighted average interest rate percentage			3.00%
Debt Instrument, Principle Advance			$ 800,000,000
LIBOR \| 2019 Term Loan Agreement
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			1.25%
Senior Notes \| 2028 Notes
Debt Instrument [Line Items]
Premium (Discount)			$ (5,000,000)	(5,000,000)
Outstanding Principal			$ 800,000,000	800,000,000
Debt Instrument, Interest Rate During Period			5.20%
Senior Notes \| 2027 Notes
Debt Instrument [Line Items]
Premium (Discount)			$ (2,000,000)	(2,000,000)
Outstanding Principal			$ 700,000,000	700,000,000
Debt Instrument, Interest Rate During Period			4.57%
Senior Notes \| Senior Notes including 2019 Notes, 2024 Notes, and 2044 Notes
Debt Instrument [Line Items]
Unamortized discount			$ (8,000,000)
Unamortized debt expense			22,000,000
Senior Notes \| 2024 Notes
Debt Instrument [Line Items]
Premium (Discount)			0	0
Outstanding Principal			$ 600,000,000	600,000,000
Debt Instrument, Interest Rate During Period			4.01%
Senior Notes \| 2044 Notes
Debt Instrument [Line Items]
Premium (Discount)			$ 0	0
Outstanding Principal			$ 550,000,000	550,000,000
Debt Instrument, Interest Rate During Period			5.08%
Senior Notes \| EOIT Senior Notes \| EOIT
Debt Instrument [Line Items]
Premium (Discount)			$ 0	1,000,000
Outstanding Principal			0	250,000,000
Senior Notes \| 2029 Notes
Debt Instrument [Line Items]
Premium (Discount)			(1,000,000)	(1,000,000)
Outstanding Principal			$ 550,000,000	550,000,000
Debt Instrument, Interest Rate During Period			4.31%
Commercial Paper
Debt Instrument [Line Items]
Commercial paper outstanding	[1]		$ 110,000,000	155,000,000
Weighted average interest rate percentage			2.29%
Premium (Discount)			$ 0	0
Revolving Credit Facility
Debt Instrument [Line Items]
Debt Issuance Costs, Line of Credit Arrangements, Net			4,000,000	4,000,000
Duration of term loan facility (in years)		5 years
Debt Instrument, Term of Extension Period		1 year
Letters of credit principal advances			300,000,000
Letters of credit outstanding amount			$ 3,000,000
Commitment fee percentage			0.20%
Premium (Discount)			$ 0	0
Outstanding Principal			$ 300,000,000	$ 0
Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Applicable margin percentage			1.50%
Minimum \| Eurodollar \| 2019 Term Loan Agreement
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					0.75%
Minimum \| Base Rate \| 2019 Term Loan Agreement
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					0.00%
Maximum \| Eurodollar \| 2019 Term Loan Agreement
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					1.50%
Maximum \| Base Rate \| 2019 Term Loan Agreement
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					0.50%

[1]	Short-term debt includes $110 million and $155 million of outstanding commercial paper as of March 31, 2020 and December 31, 2019 , respectively.

Derivative Instruments and He_3

Derivative Instruments and Hedging Activities - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Fair Value Hedges, Net	$ 0	$ 0
Designated as Hedging Instrument
Derivative [Line Items]
Cash Flow Hedges Derivative Instruments at Fair Value, Net		$ 0

Derivative Instruments and He_4

Derivative Instruments and Hedging Activities Quantitative Disclosures Related to Derivative Instruments (Details) - Not Designated as Hedging Instrument bbl in Thousands, MMBTU in Millions		3 Months Ended	12 Months Ended
		Mar. 31, 2020MMBTUbbl	Dec. 31, 2019MMBTUbbl
Natural Gas, Financial fixed futures/swaps \| Purchases
Derivative [Line Items]
Derivative, gross notional volume (TBtu) \| MMBTU	[1]	7	10
Natural Gas, Financial fixed futures/swaps \| Sales
Derivative [Line Items]
Derivative, gross notional volume (TBtu) \| MMBTU	[1]	20	19
Natural gas, Financial basis futures/swaps \| Purchases
Derivative [Line Items]
Derivative, gross notional volume (TBtu) \| MMBTU	[1]	7	11
Natural gas, Financial basis futures/swaps \| Sales
Derivative [Line Items]
Derivative, gross notional volume (TBtu) \| MMBTU	[1]	30	30
Natural gas, Financial swaptions \| Purchases
Derivative [Line Items]
Derivative, gross notional volume (TBtu) \| MMBTU	[1],[2]	0	0
Natural gas, Financial swaptions \| Sales
Derivative [Line Items]
Derivative, gross notional volume (TBtu) \| MMBTU	[1],[2]	7	2
Physical purchases/sales \| Purchases
Derivative [Line Items]
Derivative, gross notional volume (TBtu) \| MMBTU	[1]	0	0
Physical purchases/sales \| Sales
Derivative [Line Items]
Derivative, gross notional volume (TBtu) \| MMBTU	[1]	4	6
Crude oil, Financial Futures/swaps \| Purchases
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Volume \| bbl	[3]	0	0
Crude oil, Financial Futures/swaps \| Sales
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Volume \| bbl	[3]	630	990
Crude oil, Financial options \| Purchases
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Volume \| bbl	[2],[3]	0	0
Crude oil, Financial options \| Sales
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Volume \| bbl	[2],[3]	165	225
Natural gas liquids, Financial Futures/swaps \| Purchases
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Volume \| bbl	[4]	2,205	2,490
Natural gas liquids, Financial Futures/swaps \| Sales
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Volume \| bbl	[4]	2,085	2,415
Natural gas liquids, Options [Member] \| Purchases
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Volume \| bbl	[4]	0	0
Natural gas liquids, Options [Member] \| Sales
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount, Volume \| bbl	[4]	90	0
Natural gas
Derivative [Line Items]
Percent of contract with durations of one year or less		87.90%	86.60%
Percent of contracts with durations of more than one year and less than two years		12.10%	13.40%
Crude oil (for condensate)
Derivative [Line Items]
Percent of contract with durations of one year or less		77.40%	72.80%
Percent of contracts with durations of more than one year and less than two years		22.60%	27.20%
Natural gas liquids
Derivative [Line Items]
Percent of contract with durations of one year or less		82.50%	72.20%
Percent of contracts with durations of more than one year and less than two years		17.50%	27.80%

[1]	As of March 31, 2020 , 87.9% of the natural gas contracts had durations of one year or less and 12.1% had durations of more than one year and less than two years. As of December 31, 2019 , 86.6% of the natural gas contracts had durations of one year or less and 13.4% had durations of more than one year and less than two years.
[2]	.
[3]	As of March 31, 2020 , 77.4% of the crude oil (for condensate) contracts had durations of one year or less and 22.6% had durations of more than one year and less than two years. As of December 31, 2019 , 72.8% of the crude oil (for condensate) contracts had durations of one year or less and 27.2% had durations of more than one year and less than two years.
[4]	As of March 31, 2020 , 82.5% of the natural gas liquids contracts had durations of one year or less and 17.5% had durations of more than one year and less than two years. As of December 31, 2019 , 72.2% of the natural gas liquid contracts had durations of one year or less and 27.8% had durations of more than one year and less than two years.

Derivative Instruments and He_5

Derivative Instruments and Hedging Activities - Derivative Instruments Designated as Hedging Instruments (Details) - Designated as Hedging Instrument - USD ($) $ in Millions		Mar. 31, 2020	Dec. 31, 2019
Derivative [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	[1]	$ 0	$ 0
Interest Rate Swap
Derivative [Line Items]
Gross Notional Value		300	300
Other Current Assets \| Interest Rate Swap
Derivative [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement		$ 0	$ 0

[1]	All interest rate derivative instruments that were designated as cash flow hedges are considered Level 2 as of March 31, 2020 and December 31, 2019 .

Derivative Instruments and He_6

Derivative Instruments and Hedging Activities - Balance Sheet Location (Details) bbl in Millions, $ in Millions		12 Months Ended
		Dec. 31, 2019USD ($)bbl	Mar. 31, 2020USD ($)
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	[1]	$ 3	$ 9
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	[1]	0	0
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement	[2]	38	26
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement	[2]	49	47
Interest rate swaps \| Designated as Hedging Instrument \| Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement		0	0
Interest rate swaps \| Designated as Hedging Instrument \| Other Current Liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		1	5
Interest rate swaps \| Designated as Hedging Instrument \| Other Noncurrent Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement		0	0
Interest rate swaps \| Designated as Hedging Instrument \| Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		2	4
Natural gas \| Financial futures/swaps \| Not Designated as Hedging Instrument \| Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement		7	7
Natural gas \| Financial futures/swaps \| Not Designated as Hedging Instrument \| Other Current Liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		5	6
Natural gas \| Financial futures/swaps \| Not Designated as Hedging Instrument \| Other Noncurrent Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement		0	0
Natural gas \| Financial futures/swaps \| Not Designated as Hedging Instrument \| Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		1	0
Natural gas \| Physical purchases/sales \| Not Designated as Hedging Instrument \| Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement		5	4
Natural gas \| Physical purchases/sales \| Not Designated as Hedging Instrument \| Other Current Liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		0	0
Natural gas \| Financial swaptions \| Not Designated as Hedging Instrument \| Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement		$ 0	2
Natural gas \| Financial swaptions \| Not Designated as Hedging Instrument \| Other Current Liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement			1
Derivative, Nonmonetary Notional Amount, Volume \| bbl		0
Crude oil (for condensate) \| Financial futures/swaps \| Not Designated as Hedging Instrument \| Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement		$ 1	6
Crude oil (for condensate) \| Financial futures/swaps \| Not Designated as Hedging Instrument \| Other Current Liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		19	8
Crude oil (for condensate) \| Financial futures/swaps \| Not Designated as Hedging Instrument \| Other Noncurrent Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement		0	1
Crude oil (for condensate) \| Financial futures/swaps \| Not Designated as Hedging Instrument \| Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		8	5
Crude oil (for condensate) \| Financial swaptions \| Not Designated as Hedging Instrument \| Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement		0	4
Crude oil (for condensate) \| Financial swaptions \| Not Designated as Hedging Instrument \| Other Current Liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		0	0
Natural gas liquids \| Financial futures/swaps \| Not Designated as Hedging Instrument \| Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement		25	16
Natural gas liquids \| Financial futures/swaps \| Not Designated as Hedging Instrument \| Other Current Liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		3	5
Natural gas liquids \| Financial futures/swaps \| Not Designated as Hedging Instrument \| Other Noncurrent Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement		11	6
Natural gas liquids \| Financial futures/swaps \| Not Designated as Hedging Instrument \| Other Noncurrent Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		2	1
Natural gas liquids \| Financial swaptions \| Not Designated as Hedging Instrument \| Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset Including Not Subject to Master Netting Arrangement		0	1
Natural gas liquids \| Financial swaptions \| Not Designated as Hedging Instrument \| Other Current Liabilities
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability Including Not Subject to Master Netting Arrangement		$ 0	$ 0

[1]	All interest rate derivative instruments that were designated as cash flow hedges are considered Level 2 as of March 31, 2020 and December 31, 2019 .
[2]	See Note 11 for a reconciliation of the Partnership’s commodity derivatives fair value to the Partnership’s Condensed Consolidated Balance Sheets as of March 31, 2020 and December 31, 2019 .

Derivative Instruments and He_7

Derivative Instruments and Hedging Activities - Amounts Recognized in Income (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on derivative, net	$ 20	$ (10)
Change in fair value of commodity derivatives	10	(12)
Realized gain on commodity derivatives	10	2
Gain (loss) on commodity derivative activity	20	(10)
Cash collateral posted	0
Cash collateral required if ratings are lowered	0
Natural gas \| Financial futures/swaps
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on derivative, net	4	(1)
Natural gas \| Financial swaptions
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on derivative, net	(1)	0
Natural gas \| Physical purchases/sales
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on derivative, net	1	(1)
Condensate \| Financial futures/swaps
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on derivative, net	19	(11)
Condensate \| Financial swaptions
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on derivative, net	4	0
Natural gas liquids \| Financial futures/swaps
Derivative Instruments, Gain (Loss) [Line Items]
Gain (Loss) on derivative, net	$ (7)	$ 3

Fair Value Measurements - Carry

Fair Value Measurements - Carrying and Fair Value Amounts (Details) - USD ($)		Mar. 31, 2020	Dec. 31, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term debt		$ 110,000,000	$ 155,000,000
Carrying Amount \| Significant other observable inputs (Level 2) \| 2019 Term Loan Agreement \| 2019 Term Loan Agreement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
2019 Term Loan Agreement (Level 2)		800,000,000	800,000,000
Carrying Amount \| Significant other observable inputs (Level 2) \| Senior Notes \| 2024 Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes (Level 2)		600,000,000	600,000,000
Carrying Amount \| Significant other observable inputs (Level 2) \| Senior Notes \| 2027 Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes (Level 2)		698,000,000	698,000,000
Carrying Amount \| Significant other observable inputs (Level 2) \| Senior Notes \| 2028 Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes (Level 2)		795,000,000	795,000,000
Carrying Amount \| Significant other observable inputs (Level 2) \| Senior Notes \| 2029 Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes (Level 2)		549,000,000	549,000,000
Carrying Amount \| Significant other observable inputs (Level 2) \| Senior Notes \| 2044 Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes (Level 2)		550,000,000	550,000,000
Carrying Amount \| Significant other observable inputs (Level 2) \| Senior Notes \| EOIT Senior Notes \| EOIT
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes (Level 2)		0	251,000,000
Carrying Amount \| Significant other observable inputs (Level 2) \| Revolving Credit Facility \| Revolving Credit Facility
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Revolving Credit Facility (Level 2)	[1]	300,000,000	0
Fair Value \| Significant other observable inputs (Level 2) \| 2019 Term Loan Agreement \| 2019 Term Loan Agreement
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
2019 Term Loan Agreement (Level 2)		800,000,000	800,000,000
Fair Value \| Significant other observable inputs (Level 2) \| Senior Notes \| 2024 Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes (Level 2)		333,000,000	614,000,000
Fair Value \| Significant other observable inputs (Level 2) \| Senior Notes \| 2027 Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes (Level 2)		340,000,000	698,000,000
Fair Value \| Significant other observable inputs (Level 2) \| Senior Notes \| 2028 Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes (Level 2)		398,000,000	811,000,000
Fair Value \| Significant other observable inputs (Level 2) \| Senior Notes \| 2029 Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes (Level 2)		253,000,000	526,000,000
Fair Value \| Significant other observable inputs (Level 2) \| Senior Notes \| 2044 Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes (Level 2)		236,000,000	506,000,000
Fair Value \| Significant other observable inputs (Level 2) \| Senior Notes \| EOIT Senior Notes \| EOIT
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Senior Notes (Level 2)		0	252,000,000
Fair Value \| Significant other observable inputs (Level 2) \| Revolving Credit Facility \| Revolving Credit Facility
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Revolving Credit Facility (Level 2)	[1]	300,000,000	0
Commercial Paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Short-term debt	[2]	$ 110,000,000	$ 155,000,000

[1]	Borrowing capacity is effectively reduced by our borrowings outstanding under the commercial paper program. $110 million and $155 million of commercial paper was outstanding as of March 31, 2020 and December 31, 2019 , respectively.
[2]	Short-term debt includes $110 million and $155 million of outstanding commercial paper as of March 31, 2020 and December 31, 2019 , respectively.

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value Hierarchy (Details) - USD ($) $ in Millions		Mar. 31, 2020	Dec. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Retained fuel due from shippers		$ 23	$ 21
Over retained fuel due from shippers		7	8
Commodity Contracts \| Recurring Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, total fair value		47	49
Liabilities, total fair value		26	38
Assets		(26)	(37)
Liabilities		(26)	(37)
Assets		21	12
Liabilities		0	1
Commodity Contracts \| Recurring Measurement \| Quoted market prices in active market for identical assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets		5	5
Liabilities		18	31
Commodity Contracts \| Recurring Measurement \| Significant other observable inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets		42	44
Liabilities		8	7
Gas Imbalances \| Recurring Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, total fair value	[1],[2]	13	14
Liabilities, total fair value	[2],[3]	10	11
Assets	[1],[2]	0	0
Liabilities	[2],[3]	0	0
Assets	[1],[2]	13	14
Liabilities	[2],[3]	10	11
Gas Imbalances \| Recurring Measurement \| Quoted market prices in active market for identical assets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	[1],[2]	0	0
Liabilities	[2],[3]	0	0
Gas Imbalances \| Recurring Measurement \| Significant other observable inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets	[1],[2]	13	14
Liabilities	[2],[3]	$ 10	$ 11

[1]	Gas imbalance assets exclude fuel reserves for under retained fuel due from shippers of $23 million and $21 million at March 31, 2020 and December 31, 2019 , respectively, which fuel reserves are based on the value of natural gas at the time the imbalance was created, and which are not subject to revaluation at fair market value.
[2]	The Partnership uses the market approach to fair value its gas imbalance assets and liabilities at individual, or where appropriate an average of, current market indices applicable to the Partnership’s operations, not to exceed net realizable value. There were no netting adjustments as of March 31, 2020 and December 31, 2019 .
[3]	Gas imbalance liabilities exclude fuel reserves for over retained fuel due to shippers of $7 million and $8 million at March 31, 2020 and December 31, 2019 , respectively, which fuel reserves are based on the value of natural gas at the time the imbalance was created, and which are not subject to revaluation at fair market value.

Supplemental Disclosure of Ca_3

Supplemental Disclosure of Cash Flow Information - Supplemental Disclosure of Cash Flow Information (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Interest, net of capitalized interest	$ 43	$ 32
Accounts payable related to capital expenditures	8	39
Lease liabilities related to (derecognition) recognition of right-of-use assets	(4)
Lease liabilities related to (derecognition) recognition of right-of-use assets		$ 35
Cumulative Effect, Period of Adoption, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Impact of adoption of financial instruments-credit losses	(3)
Accounting Standards Update 2016-13 [Member] \| Cumulative Effect, Period of Adoption, Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Impact of adoption of financial instruments-credit losses	$ (3)

Supplemental Disclosure of Ca_4

Supplemental Disclosure of Cash Flow Information - Reconciliation of Cash and Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Supplemental Cash Flow Information [Abstract]
Cash and cash equivalents	$ 4	$ 4	$ 18
Restricted cash	0		1
Cash, cash equivalents and restricted cash shown in the Condensed Consolidated Statements of Cash Flows	$ 4	$ 4	$ 19	$ 22

Related Party Transactions - Na

Related Party Transactions - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Related Party Transaction [Line Items]
Partnership's revenues from affiliated companies as a percent of total revenues	8.00%	6.00%
Subsidiary of Common Parent \| CenterPoint \| Three Services Included in Transportation and Storage Agreements
Related Party Transaction [Line Items]
Period of written notice	180 days
CenterPoint and OGE Energy \| Minimum
Related Party Transaction [Line Items]
Period notice of termination for reimbursements for all employee costs	90 days
OGE Energy \| Defined Benefit and Retiree Medical Plans
Related Party Transaction [Line Items]
Expense reimbursement, 2018 and thereafter	$ 5
OGE Energy \| Certain Services and Support Functions
Related Party Transaction [Line Items]
Expense reimbursement annual caps	1
CenterPoint \| Certain Services and Support Functions
Related Party Transaction [Line Items]
Expense reimbursement annual caps	$ 0

Related Party Transactions - Re

Related Party Transactions - Related Party Activity (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Related Party Transaction [Line Items]
Revenues from affiliated companies	$ 51	$ 48
Cost of goods sold from affiliate	9	6
CenterPoint
Related Party Transaction [Line Items]
Cost of goods sold from affiliate	1	0
CenterPoint \| Gas Transportation and Storage
Related Party Transaction [Line Items]
Revenues from affiliated companies	37	33
CenterPoint \| Gas Sales
Related Party Transaction [Line Items]
Revenues from affiliated companies	0	1
OGE Energy
Related Party Transaction [Line Items]
Cost of goods sold from affiliate	8	6
OGE Energy \| Gas Transportation and Storage
Related Party Transaction [Line Items]
Revenues from affiliated companies	9	13
OGE Energy \| Gas Sales
Related Party Transaction [Line Items]
Revenues from affiliated companies	5	1
OGE Energy \| Seconded Employee Costs
Related Party Transaction [Line Items]
Charges to the Partnership by affiliates	$ 3	$ 6

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Millions	Apr. 01, 2020USD ($)	Sep. 13, 2018	Jan. 01, 2017MMcf	Mar. 31, 2020USD ($)
Gathering and processing agreement term (in years)			10 years
Energy deliveries (in MMcf/d) \| MMcf			400
Minimum volume commitment fee				$ 187
Minimum volume commitment fees remaining in 2020				15
Minimum volume commitment fees per year from 2021 through 2027				23
Minimum volume commitment fees in 2028				11
Estimated Cost to Complete Pipeline Project				$ 500
Firm transportation service agreement term (in years)		20 years
Subsequent Event \| Forecast
Sale of interest	$ 19

Equity-Based Compensation (Deta

Equity-Based Compensation (Details) - USD ($) $ in Millions	3 Months Ended
Equity-Based Compensation (Details) - USD ($) $ in Millions	Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation expense	$ 4	$ 4
Performance units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation expense	2	3
Phantom units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total compensation expense	$ 2	$ 1

Equity-Based Compensation - Sch

Equity-Based Compensation - Schedule of Assumptions Related to Performance Share Units (Details) - Performance units	3 Months Ended
	Mar. 31, 2020$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period	381,981	[1]
Number of units granted	933,738	[2]
Fair value of units granted \| $ / shares	$ 7	[2]
Expected distribution yield	27.70%
Expected price volatility	0.85%
Risk-free interest rate	12.27%
Expected life of units (in years)	3 years

[1]	Performance units vested as of March 31, 2020 include 376,292 units from the 2017 annual grant, which were approved by the Board of Directors in 2017 and, based on the level of achievement of a performance goal established by the Board of Directors over the performance period of January 1, 2017 through December 31, 2019
[2]	Performance units represents the target number of performance units granted. The actual number of performance units earned, if any, is dependent upon performance and may range from 0% to 200% of the target.

Equity-Based Compensation - Pha

Equity-Based Compensation - Phantom Units (Details)	3 Months Ended
Equity-Based Compensation - Phantom Units (Details)	Mar. 31, 2020$ / sharesshares
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of phantom units granted (in dollars per share)	$ 6.48
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of phantom units granted (in dollars per share)	$ 10.13
Phantom units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Phantom Units granted \| shares	941,732	[1]
Fair value of phantom units granted (in dollars per share)	$ 8.41	[1]

[1]	Performance units represents the target number of performance units granted. The actual number of performance units earned, if any, is dependent upon performance and may range from 0% to 200% of the target.

Equity-Based Compensation - Equ

Equity-Based Compensation - Equity Units Activity (Details) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)$ / sharesshares
Minimum
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Granted (in dollars per unit)	$ 6.48
Maximum
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Granted (in dollars per unit)	$ 10.13
Performance units
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Units Outstanding (in units) \| shares	1,393,329
Granted (in units) \| shares	933,738	[1]
Vested (in units) \| shares	(381,981)	[2]
Forfeited (in units) \| shares	(11,621)
Units Outstanding (in units) \| shares	1,933,465
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Units Outstanding (in dollars per unit)	$ 19.04
Granted (in dollars per unit)	7	[1]
Vested (in dollars per unit)	19.25	[2]
Forfeited (in dollars per unit)	19.12
Units Outstanding (in dollars per unit)	$ 13.18
Aggregate Intrinsic Value of Units Outstanding \| $	$ 5
Performance units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Payout percentage	0.00%
Performance units \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Payout percentage	200.00%
Performance units \| Annual Grant in 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Granted (in units) \| shares	376,292
Phantom units
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Units Outstanding (in units) \| shares	1,392,560
Granted (in units) \| shares	941,732	[1]
Vested (in units) \| shares	(347,287)	[2]
Forfeited (in units) \| shares	(10,611)
Units Outstanding (in units) \| shares	1,976,394
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Units Outstanding (in dollars per unit)	$ 14.65
Granted (in dollars per unit)	8.41	[1]
Vested (in dollars per unit)	16.10	[2]
Forfeited (in dollars per unit)	14.81
Units Outstanding (in dollars per unit)	$ 10.55
Aggregate Intrinsic Value of Units Outstanding \| $	$ 5

[1]	Performance units represents the target number of performance units granted. The actual number of performance units earned, if any, is dependent upon performance and may range from 0% to 200% of the target.
[2]	Performance units vested as of March 31, 2020 include 376,292 units from the 2017 annual grant, which were approved by the Board of Directors in 2017 and, based on the level of achievement of a performance goal established by the Board of Directors over the performance period of January 1, 2017 through December 31, 2019

Equity-Based Compensation - Unr

Equity-Based Compensation - Unrecognized Compensation Cost (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Cost (In millions)	$ 29
Performance units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Cost (In millions)	$ 16
Weighted Average Period for Recognition (In years)	2 years 2 months 4 days
Phantom units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation Cost (In millions)	$ 13
Weighted Average Period for Recognition (In years)	1 year 11 months 19 days
Long Term Incentive Plan \| Common Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for issuance \| shares	4,987,106

Reportable Segments - Schedule

Reportable Segments - Schedule of Financial Data for Business Segments and Services (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020USD ($)segment	Mar. 31, 2019USD ($)	Dec. 31, 2019USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment	2
Total Revenues	$ 648	$ 795
Cost of natural gas and natural gas liquids (excluding depreciation and amortization shown separately)	226	378
Operation and maintenance, General and administrative	126	129
Depreciation and amortization	104	105
Impairments	28	0
Taxes other than income tax	18	18
Operating Income	146	165
Capital expenditures	54	143
Total assets	12,117		$ 12,266
Operating Segments \| Gathering and Processing
Segment Reporting Information [Line Items]
Total Revenues	477	630
Cost of natural gas and natural gas liquids (excluding depreciation and amortization shown separately)	211	360
Operation and maintenance, General and administrative	81	84
Depreciation and amortization	74	74
Impairments	28
Taxes other than income tax	11	11
Operating Income	72	101
Capital expenditures	34	107
Total assets	9,659		9,739
Operating Segments \| Transportation and Storage
Segment Reporting Information [Line Items]
Total Revenues	234	316
Cost of natural gas and natural gas liquids (excluding depreciation and amortization shown separately)	78	169
Operation and maintenance, General and administrative	45	45
Depreciation and amortization	30	31
Impairments	0
Taxes other than income tax	7	7
Operating Income	74	64
Capital expenditures	20	36
Total assets	5,702		5,886
Eliminations
Segment Reporting Information [Line Items]
Total Revenues	(63)	(151)
Cost of natural gas and natural gas liquids (excluding depreciation and amortization shown separately)	(63)	(151)
Operation and maintenance, General and administrative	0	0
Depreciation and amortization	0	0
Impairments	0
Taxes other than income tax	0	0
Operating Income	0	0
Capital expenditures	0	0
Total assets	(3,244)		$ (3,359)
Product
Segment Reporting Information [Line Items]
Total Revenues	288	443
Product \| Operating Segments \| Gathering and Processing
Segment Reporting Information [Line Items]
Total Revenues	275	423
Product \| Operating Segments \| Transportation and Storage
Segment Reporting Information [Line Items]
Total Revenues	75	167
Product \| Eliminations
Segment Reporting Information [Line Items]
Total Revenues	(62)	(147)
Natural Gas, Gathering, Transportation, Marketing and Processing
Segment Reporting Information [Line Items]
Total Revenues	360	352
Natural Gas, Gathering, Transportation, Marketing and Processing \| Operating Segments \| Gathering and Processing
Segment Reporting Information [Line Items]
Total Revenues	202	207
Natural Gas, Gathering, Transportation, Marketing and Processing \| Operating Segments \| Transportation and Storage
Segment Reporting Information [Line Items]
Total Revenues	159	149
Natural Gas, Gathering, Transportation, Marketing and Processing \| Eliminations
Segment Reporting Information [Line Items]
Total Revenues	$ (1)	$ (4)

Subsequent Event (Details)

Subsequent Event (Details) $ in Millions	Apr. 08, 2020USD ($)
Gathering and Processing \| Subsequent Event
Subsequent Event [Line Items]
Impairment of Property, Plant and Equipment	$ 20