Organization and Summary of Significant Accounting Policies (Composition of Net Unevaluated Costs Excluded from Amortization) (Details) - USD ($) $ in Millions	12 Months Ended			204 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Capitalized Costs of Unproved Properties Excluded from Amortization, Period Cost [Abstract]
Property acquisition costs	$ 63	$ 86	$ 559	$ 1,005
Exploration and development costs	24	9	8	18
Capitalized interest	115	91	75	22
Net unevaluated costs excluded from amortization	202	186	$ 642	$ 1,045
Capitalized Costs of Unproved Properties Excluded from Amortization, Cumulative [Abstract]
Property acquisition costs	1,713
Exploration and development costs	59
Capitalized interest	303
Net unevaluated costs excluded from amortization, cumulative	$ 2,075	$ 2,217