Segment Information - Reconciliation to Net Income (Details) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2020		Jun. 30, 2019		Jun. 30, 2020		Jun. 30, 2019
Segment Reporting, Revenue Reconciling Item [Line Items]
Depreciation and amortization	$ 321	[1]	$ 313	[1],[2],[3]	$ 646		$ 614	[2],[4]
Income Tax Expense (Benefit)	0		1	[2],[3]	0		2	[2]
Amortization of Debt Issuance Costs					(29)		(19)	[4]
Share-based Payment Arrangement, Expense	(3)		(5)	[3]	(8)		(12)
Goodwill and Intangible Asset Impairment	0		0	[2],[3]	(2,165)		0	[2],[4]
Interest and Other Financial Costs	(208)		(217)	[3]	(424)		(434)
Income/(loss) from equity method investments(2)	89		83	[2],[3]	(1,095)	[5],[6]	160	[2],[4]
Proceeds from Equity Method Investment, Distribution, Return of Capital					(226)		(245)	[4]
Acquisition Costs, Period Cost	0		(4)	[3]	0		(5)
Other Cost and Expense, Operating	1		0	[3]	2		0
Net income	655		657	[2],[3],[7]	(2,061)		1,346	[2],[4],[7]
Operating Segments
Segment Reporting, Revenue Reconciling Item [Line Items]
Adjusted EBITDA	1,227		920	[3]	2,521		1,850
Amortization of Debt Issuance Costs	(15)		(12)	[3]	(29)		(19)
Segment Reconciling Items [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Proceeds from Equity Method Investment, Distribution, Return of Capital	(115)		(132)	[3]	(239)		(254)
Adjusted EBITDA attributable to noncontrolling interests	8		7	[3]	17		14
L&S
Segment Reporting, Revenue Reconciling Item [Line Items]
Depreciation and amortization	138		134		276		260
L&S | Operating Segments
Segment Reporting, Revenue Reconciling Item [Line Items]
Adjusted EBITDA	839	[8]	570	[3],[8]	1,711		1,129
Income/(loss) from equity method investments(2)	40		54	[3]	90		99
G&P
Segment Reporting, Revenue Reconciling Item [Line Items]
Depreciation and amortization	183		179		370		354
G&P | Operating Segments
Segment Reporting, Revenue Reconciling Item [Line Items]
Adjusted EBITDA	388	[8]	350	[3],[8]	810		721
Income/(loss) from equity method investments(2)	49		29	[3]	(1,185)		61
Not Designated as Hedging Instrument [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Unrealized Gain (Loss) on Derivatives and Commodity Contracts	$ (6)	[8]	$ 0	[3],[8]	$ 9		$ (4)

[1] Within the total segment revenues and other income amounts presented above, third party revenues for the L&S segment were $146 million and $304 million for the three and six months ended June 30, 2020, respectively, and $163 million and $316 million for the three and six months ended June 30, 2019, respectively. Third party revenues for the G&P segment were $748 million and $323 million for the three and six months ended June 30, 2020, respectively, and $851 million and $1,738 million for the three and six months ended June 30, 2019, respectively.

[2] Financial information for the three and six months ended June 30, 2019 has been retrospectively adjusted for the acquisition of ANDX. See Notes 1 and 3.

[3] Financial information for the three and six months ended June 30, 2019 has been retrospectively adjusted for the acquisition of ANDX. See Notes 1 and 3.

[4] Financial information for the six months ended June 30, 2019 has been retrospectively adjusted for the acquisition of ANDX. See Notes 1 and 3.

[5] The 2020 period includes $1,264 million of impairment expense. See Note 4.

[6] The six months ended June 30, 2020 includes $1,264 million of impairment expense. See Note 4.

[7] Financial information for the three and six months ended June 30, 2019 has been retrospectively adjusted for the acquisition of ANDX. See Notes 1 and 3.

[8] See below for the reconciliation from Segment Adjusted EBITDA to net income.