Acquisition and Divestiture - (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
Derivative assets	2
Evaluated natural gas and oil properties	2,724
Unevaluated natural gas and oil properties	684
Other property, plant and equipment	4
Other long-term assets	27
Total assets acquired	3,690
Fair Value of Liabilities Assumed:
Accounts payable	274
Other current liabilities	55
Derivative liabilities	501
Revolving credit facility	95
Senior unsecured notes	726
Asset retirement obligations	8
Other long-term liabilities	70
Total liabilities assumed	1,729
Net assets acquired and liabilities assumed	1,961
Purchase price adjustment	$ 8