CONSOLIDATED STATEMENTS OF CHANGES IN PARTNERS' CAPITAL - USD ($) $ in Millions	Total	Partners’ Capital Excluding Noncontrolling Interests	Noncontrolling Interests	Series A Preferred Units Limited Partners Partners’ Capital Excluding Noncontrolling Interests	Series B Preferred Units Limited Partners Partners’ Capital Excluding Noncontrolling Interests	Common Units Limited Partners Partners’ Capital Excluding Noncontrolling Interests
Balance, beginning of period at Dec. 31, 2018	$ 12,002	$ 12,002		$ 1,505	$ 787	$ 9,710
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income/(loss)	2,180	2,171	$ 9	149	49	1,973
Distributions (Note 12)	(1,208)	(1,202)	(6)	(149)	(49)	(1,004)
Other comprehensive income	97	97				97
Equity-indexed compensation expense	17	17				17
Sale of noncontrolling interest in a subsidiary (Note 12)	128	(2)	130			(2)
Other	(21)	(21)				(21)
Balance, end of period at Dec. 31, 2019	13,195	13,062	133	1,505	787	10,770
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income/(loss)	(2,580)	(2,590)	10	149	49	(2,788)
Distributions (Note 12)	(863)	(853)	(10)	(149)	(49)	(655)
Other comprehensive income	15	15				15
Equity-indexed compensation expense	19	19				19
Repurchase of common units (Note 12)	(50)	(50)				(50)
Partners' Capital Account, Contributions (Note 12)	12		12
Other	(10)	(10)				(10)
Balance, end of period at Dec. 31, 2020	9,738	9,593	145	1,505	787	7,301
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income/(loss)	648	593	55	149	49	395
Distributions (Note 12)	(729)	(715)	(14)	(149)	(49)	(517)
Other comprehensive income	65	65				65
Equity-indexed compensation expense	19	19				19
Repurchase of common units (Note 12)	(178)	(178)				(178)
Partners' Capital Account, Contributions (Note 12)	1		1
Plains Oryx Permian Basin LLC joint venture formation (Note 7)	3,256	605	2,651			605
Other	(10)	(10)				(10)
Balance, end of period at Dec. 31, 2021	$ 12,810	$ 9,972	$ 2,838	$ 1,505	$ 787	$ 7,680