Equity Method Investments - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Schedule of Equity Method Investments [Line Items]
Distributions received from equity method investments	$ 111	$ 123
Unamortized basis differences included in equity investments	73		$ 75
Amortization expense	2	2
Equity method investments	979		974
Poseidon
Schedule of Equity Method Investments [Line Items]
Equity method investments	0		0
Investment, excess distribution	8	14
Permian Basin
Schedule of Equity Method Investments [Line Items]
Equity method investments	79		$ 80
Capital contribution	$ 0	$ 2