Derivative and Hedging Activities - Derivative Instruments (Details) - Energy related derivative $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($) MMBbls Bcf	Dec. 31, 2020 USD ($) Bcf MMBbls
Derivative [Line Items]
Total derivatives	$ (1,143)	$ (118)
Oil
Derivative [Line Items]
Notional, volume | MMBbls	22,000,000	34
Total derivatives	$ (358)	$ (137)
Oil | Fixed-price swaps
Derivative [Line Items]
Notional, volume | MMBbls	13,000,000	27
Total derivatives	$ (356)	$ (136)
Oil | Basis protection swaps
Derivative [Line Items]
Notional, volume | MMBbls	9,000,000	7
Total derivatives	$ (2)	$ (1)
Natural gas
Derivative [Line Items]
Notional, volume | Bcf	1,112,000,000	847
Total derivatives	$ (785)	$ 19
Natural gas | Fixed-price swaps
Derivative [Line Items]
Notional, volume | Bcf	637,000,000	728
Total derivatives	$ (675)	$ 10
Natural gas | Collars
Derivative [Line Items]
Notional, volume | Bcf	205,000,000	53
Total derivatives	$ (82)	$ 8
Natural gas | Call options
Derivative [Line Items]
Notional, volume | Bcf	18,000,000	0
Total derivatives	$ (17)	$ 0
Natural gas | Basis protection swaps
Derivative [Line Items]
Notional, volume | Bcf	252,000,000	66
Total derivatives	$ (11)	$ 1