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Amount of ownership interest in limited liability company (LLC), attributable to the parent entity.

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Amount of increase in noncontrolling interest from a business combination.

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Change in the different classes of partners' capital accounts during the year due to acquisitions. Partners include general, limited and preferred partners.

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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, 2021
Business Acquisition [Line Items]
Partners' capital increase from business combination		$ 3,256
Noncontrolling Interests
Business Acquisition [Line Items]
Partners' capital increase from business combination		$ 3,090
Plains Oryx Permian Basin LLC (Permian JV) \| Joint Venture Formation
Business Acquisition [Line Items]
Partners' capital increase from business combination	$ 3,256
Plains Oryx Permian Basin LLC (Permian JV) \| Joint Venture Formation \| Plains Oryx Permian Basin LLC (Permian JV)
Business Acquisition [Line Items]
Net assets of joint venture	7,575
Plains Oryx Permian Basin LLC (Permian JV) \| Joint Venture Formation \| Class A Shares
Business Acquisition [Line Items]
Partners' capital increase from business combination	166
Plains Oryx Permian Basin LLC (Permian JV) \| Joint Venture Formation \| Noncontrolling Interests
Business Acquisition [Line Items]
Noncontrolling Interest, Increase from Business Combination	3,090
Plains Oryx Permian Basin LLC (Permian JV) \| Joint Venture Formation \| Noncontrolling Interests \| Oryx Midstream Holdings LLC
Business Acquisition [Line Items]
Noncontrolling Interest, Increase from Business Combination	2,651
Plains Oryx Permian Basin LLC (Permian JV) \| Joint Venture Formation \| Noncontrolling Interests \| PAA and AAP
Business Acquisition [Line Items]
Noncontrolling Interest, Increase from Business Combination	$ 439