Acquisition - (Schedule of the Allocation of Purchase Price of Indigo) (Details) - Indigo Natural Resources, LLC $ in Millions	Sep. 01, 2021 USD ($)
Consideration:
Total consideration	$ 1,961
Fair Value of Assets Acquired:
Cash and cash equivalents	55
Accounts receivable	192
Other current assets	2
Commodity derivative assets	2
Evaluated oil and gas properties	2,724
Unevaluated oil and gas properties	676
Other property, plant and equipment	4
Other long-term assets	27
Total assets acquired	3,682
Fair Value of Liabilities Assumed:
Accounts payable	266
Other current liabilities	55
Derivative liabilities	501
Revolving credit facility	95
Senior unsecured notes	726
Asset retirement obligations	8
Other noncurrent liabilities	70
Total liabilities assumed	1,721
Net Assets Acquired and Liabilities Assumed	$ 1,961