Variable Interest Entities (Consolidated Information of Variable Interest Entity) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Variable Interest Entity [Line Items]
Cash and cash equivalents	$ 571	$ 164
Accounts receivable	1,009	1,564
Prepayments and other current assets	130	113
Plant, property, and equipment, net	23,003	22,713
Total assets	31,386	31,353
Accounts payable	679	928
Asset retirement obligations	762	746
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Cash and cash equivalents	21	28
Accounts receivable	3	7
Prepayments and other current assets	4	3
Plant, property, and equipment, net	818	825
Total assets	846	863
Accounts payable	4	15
Asset retirement obligations	24	24
Total liabilities	$ 28	$ 39