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Acquisitions, Divestitures and Other Transactions - Partners' Capital (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Oct. 31, 2021	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2023
Plains Oryx Permian Basin LLC
Business Acquisition [Line Items]
Noncontrolling interest, ownership (as a percent)				35.00%
Joint Venture Formation \| Oryx Midstream Holdings LLC \| Plains Oryx Permian Basin LLC
Business Acquisition [Line Items]
Noncontrolling interest, ownership (as a percent)	35.00%
Plains Oryx Permian Basin LLC \| Joint Venture Formation
Business Acquisition [Line Items]
Partners' capital impact of business combination	$ 3,230	$ (26)	$ 3,256
Plains Oryx Permian Basin LLC \| Joint Venture Formation \| Class A Shares
Business Acquisition [Line Items]
Partners' capital impact of business combination	163
Plains Oryx Permian Basin LLC \| Joint Venture Formation \| Noncontrolling Interests
Business Acquisition [Line Items]
Noncontrolling interest, increase from business combination	3,067
Partners' capital impact of business combination		$ (23)	$ 3,090
Plains Oryx Permian Basin LLC \| Joint Venture Formation \| Noncontrolling Interests \| PAA and AAP
Business Acquisition [Line Items]
Noncontrolling interest, increase from business combination	432
Plains Oryx Permian Basin LLC \| Joint Venture Formation \| Oryx Midstream Holdings LLC \| Noncontrolling Interests
Business Acquisition [Line Items]
Noncontrolling interest, increase from business combination	$ 2,635