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Partners' Capital and Distributions - Consolidated Subsidiaries (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Nov. 30, 2022	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Nov. 30, 2020
Common Equity Repurchase Program
Subsidiary, Sale of Stock [Line Items]
Common equity repurchase program, authorized amount					$ 500
Common Equity Repurchase Program \| PAA
Subsidiary, Sale of Stock [Line Items]
Total purchase price of PAA common units repurchased		$ 0	$ 0	$ 74
Common equity repurchase program, remaining amount		$ 198
Cactus II Pipeline LLC
Subsidiary, Sale of Stock [Line Items]
Additional interest acquired (as a percent)	5.00%
Business combination, step acquisition, equity interest in acquiree, including subsequent acquisition (as a percent)	70.00%
Cactus II Pipeline LLC \| Noncontrolling Interests
Subsidiary, Sale of Stock [Line Items]
Noncontrolling interest, increase from business combination	$ 526
PAA \| Common Units and Series A Preferred Units
Subsidiary, Sale of Stock [Line Items]
Noncontrolling interest, ownership (as a percent)		70.00%
PAA \| Series B Preferred Units
Subsidiary, Sale of Stock [Line Items]
Noncontrolling interest, ownership (as a percent)		100.00%
AAP
Subsidiary, Sale of Stock [Line Items]
Noncontrolling interest, ownership (as a percent)		15.00%
Plains Oryx Permian Basin LLC
Subsidiary, Sale of Stock [Line Items]
Noncontrolling interest, ownership (as a percent)		35.00%
Cactus II Pipeline LLC
Subsidiary, Sale of Stock [Line Items]
Noncontrolling interest, ownership (as a percent)		30.00%
Cactus II Pipeline LLC \| Enbridge
Subsidiary, Sale of Stock [Line Items]
Noncontrolling interest, ownership (as a percent)	30.00%
Red River
Subsidiary, Sale of Stock [Line Items]
Noncontrolling interest, ownership (as a percent)		33.00%