The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Variable Interest Entities (Pipeline Investments) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Variable Interest Entities [Line Items]
Net (Loss) Income	$ (1,968)	$ 44	$ (1,924)	$ 87
Investments in joint ventures	861		861		$ 1,936
VIE not primary beneficiary
Variable Interest Entities [Line Items]
Investments in joint ventures	$ 414		$ 414		1,479
ACP
Variable Interest Entities [Line Items]
Ownership percentage	47.00%		47.00%
ACP \| VIE not primary beneficiary
Variable Interest Entities [Line Items]
Net (Loss) Income	$ (4,414)	$ 61	$ (4,342)	$ 114
Investments in joint ventures	$ (920)		$ (920)		1,179
Constitution
Variable Interest Entities [Line Items]
Ownership percentage	24.00%		24.00%
Pipeline Investments \| VIE not primary beneficiary
Variable Interest Entities [Line Items]
Investments in joint ventures	$ (920)		$ (920)		$ 1,179