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Acquisitions, Divestitures and Asset Impairments (Details) - USD ($) $ in Millions	1 Months Ended		3 Months Ended	6 Months Ended
	Apr. 30, 2020	Feb. 29, 2020	Mar. 31, 2020	Dec. 31, 2020
Business Acquisition [Line Items]
Payments to acquire businesses			$ 308
Proceeds from sale of assets			$ 104
Level 3 \| Measurement Input, Discount Rate \| Valuation Technique, Discounted Cash Flow
Business Acquisition [Line Items]
Discount rate, asset impairment analysis, cost of capital, theoretical market participant			14.00%
(Gains)/losses on asset sales and asset impairments, net
Business Acquisition [Line Items]
Non-cash impairment losses upon classification as assets held for sale			$ 167
Non-cash asset impairment losses, held and used			446
Transportation and Facilities Segments
Business Acquisition [Line Items]
Non-cash asset impairment losses			$ 489
FM Gathering LLC
Business Acquisition [Line Items]
Payments to acquire businesses		$ 300
Property and equipment acquired		115
Intangible assets acquired		$ 187
FM Gathering LLC \| Minimum \| Level 3 \| Measurement Input, Discount Rate \| Valuation Technique, Discounted Cash Flow
Business Acquisition [Line Items]
Discount rate, intangible assets, estimate of risk, theoretical market participant			15.00%
FM Gathering LLC \| Maximum \| Level 3 \| Measurement Input, Discount Rate \| Valuation Technique, Discounted Cash Flow
Business Acquisition [Line Items]
Discount rate, intangible assets, estimate of risk, theoretical market participant			16.00%
Saddlehorn Pipeline Company, LLC
Business Acquisition [Line Items]
Ownership percentage sold		10.00%
Proceeds from sale of interest in unconsolidated entity		$ 78
Saddlehorn Pipeline Company, LLC \| Gain on/(impairment of) investments in unconsolidated entities, net [Member]
Business Acquisition [Line Items]
Gain on sale of investment in unconsolidated entity		$ 21
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Other current assets
Business Acquisition [Line Items]
Assets held for sale			$ 333
Los Angeles Basin Crude Oil Terminals \| Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Forecast
Business Acquisition [Line Items]
Proceeds from sale of assets				$ 195
NGL Terminals \| Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Subsequent Event
Business Acquisition [Line Items]
Proceeds from sale of assets	$ 163