Derivative Instruments - Effect of Derivative Instruments on the Condensed Consolidated Statement of Operations (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Effect of derivative instruments on the Consolidated Balance Sheet
Total	$ (16)	$ (12)	$ (16)	$ 126
Gas contracts
Effect of derivative instruments on the Consolidated Balance Sheet
Cash received (paid) on settlement of derivative instruments	36	82	63	181
Non-cash loss on derivative instruments	(50)	(96)	(43)	(54)
Oil contracts
Effect of derivative instruments on the Consolidated Balance Sheet
Cash received (paid) on settlement of derivative instruments	0	2	(1)	3
Non-cash loss on derivative instruments	$ (2)	$ 0	$ (35)	$ (4)