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Acquisitions, Divestitures and Other Transactions (Details) $ in Millions	1 Months Ended	3 Months Ended			6 Months Ended
	Jun. 30, 2021 USD ($) plant	Dec. 31, 2021	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Business Acquisition [Line Items]
Gain on divestiture of assets			$ (369)	$ 1	$ (370)	$ (618)
Deferred losses on hedges remaining in other comprehensive income	$ 11,061		11,061	11,253	11,061	11,253	$ 11,499	$ 11,190	$ 11,186	$ 14,485
Derivative Instruments
Business Acquisition [Line Items]
Deferred losses on hedges remaining in other comprehensive income	(223)		(223)	$ (315)	(223)	$ (315)		$ (258)		$ (259)
Disposal Group, Held-for-sale, Not Discontinued Operations \| Pine Prairie and Southern Pines Natural Gas Storage Facilities \| Derivative Instruments
Business Acquisition [Line Items]
Deferred losses on hedges remaining in other comprehensive income	18		18		18
Disposal Group, Held-for-sale, Not Discontinued Operations \| Pine Prairie and Southern Pines Natural Gas Storage Facilities \| Other current assets
Business Acquisition [Line Items]
Assets held for sale, current	832		832		832
Disposal Group, Held-for-sale, Not Discontinued Operations \| Pine Prairie and Southern Pines Natural Gas Storage Facilities \| (Gains)/losses on asset sales and asset impairments, net
Business Acquisition [Line Items]
Non-cash impairment losses upon classification to assets held for sale			475
Facilities \| Disposal Group, Held-for-sale, Not Discontinued Operations \| Pine Prairie and Southern Pines Natural Gas Storage Facilities
Business Acquisition [Line Items]
Consideration to be received for sale of assets	850		$ 850		$ 850
Asset Exchange Transaction \| Inter Pipeline Ltd \| Transportation \| (Gains)/losses on asset sales and asset impairments, net
Business Acquisition [Line Items]
Gain on divestiture of assets	106
Joint Venture Transaction \| Oryx Midstream Holdings LLC \| Forecast \| Plains Oryx Permian Basin LLC \| PAA
Business Acquisition [Line Items]
Ownership interest		65.00%
Additional Interests in Straddle Plants \| Asset Exchange Transaction \| Inter Pipeline Ltd
Business Acquisition [Line Items]
Cash consideration, including working capital and other adjustments	$ 32
Additional Interests in Straddle Plants \| Asset Exchange Transaction \| Inter Pipeline Ltd \| Facilities
Business Acquisition [Line Items]
Number of straddle plants, additional interests acquired \| plant	2