Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Percentage of voting equity interests acquired in a business combination achieved in stages, including equity interests in the acquiree held by the acquirer immediately before the acquisition date and acquired at the acquisition date.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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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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Amount of stock repurchase plan authorized.

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Amount remaining of a stock repurchase plan authorized.

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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Partners' Capital and Distributions - Consolidated Subsidiaries (Details) - USD ($) $ in Millions	1 Months Ended		12 Months Ended
	Nov. 30, 2022	Oct. 31, 2021	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Nov. 30, 2020
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%
Partners' capital impact of business combination				$ 526
Common Equity Repurchase Program
Subsidiary, Sale of Stock [Line Items]
Common equity repurchase program, authorized amount						$ 500
Noncontrolling Interests \| Cactus II Pipeline LLC
Subsidiary, Sale of Stock [Line Items]
Noncontrolling interest, increase from business combination	$ 526
Partners' capital impact of business combination				526
PAA \| Common Equity Repurchase Program
Subsidiary, Sale of Stock [Line Items]
Total purchase price of PAA common units repurchased			$ 0	74	$ 178
Common equity repurchase program, remaining amount			$ 198
Joint Venture Formation \| Plains Oryx Permian Basin LLC
Subsidiary, Sale of Stock [Line Items]
Partners' capital impact of business combination		$ 3,230		(26)	3,256
Joint Venture Formation \| Noncontrolling Interests \| Plains Oryx Permian Basin LLC
Subsidiary, Sale of Stock [Line Items]
Noncontrolling interest, increase from business combination		3,067
Partners' capital impact of business combination				$ (23)	$ 3,090
Joint Venture Formation \| Partners’ Capital \| Plains Oryx Permian Basin LLC
Subsidiary, Sale of Stock [Line Items]
Partners' capital impact of business combination		$ 163
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)			16.00%
Plains Oryx Permian Basin LLC
Subsidiary, Sale of Stock [Line Items]
Noncontrolling interest, ownership (as a percent)			35.00%
Plains Oryx Permian Basin LLC \| Oryx Midstream Holdings LLC \| Joint Venture Formation
Subsidiary, Sale of Stock [Line Items]
Noncontrolling interest, ownership (as a percent)		35.00%
Noncontrolling interest, ownership percentage by parent (as a percent)		65.00%
Red River
Subsidiary, Sale of Stock [Line Items]
Noncontrolling interest, ownership (as a percent)			33.00%
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%