Condensed Consolidated Statements of Partners' Equity (Unaudited) - USD ($) shares in Millions, $ in Millions	Total	Noncontrolling Interest	Series A Preferred Units Preferred Units	Common Units Partners' Capital	AOCI Attributable to Parent	Cumulative Effect, Period of Adoption, Adjustment	Cumulative Effect, Period of Adoption, Adjustment Common Units Partners' 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)