CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME/(LOSS) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income/(loss)	$ (2,580)	$ 2,180	$ 2,216
Other comprehensive income/(loss)	15	97	(260)
Comprehensive income/(loss)	(2,565)	2,277	1,956
Comprehensive income attributable to noncontrolling interests	(10)	(9)
Comprehensive income/(loss) attributable to PAA	$ (2,575)	$ 2,268	$ 1,956