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Asset Impairments (Details) - USD ($) $ in Millions	3 Months Ended						12 Months Ended
Asset Impairments (Details) - USD ($) $ in Millions	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021	Jun. 30, 2021	Sep. 30, 2020	Mar. 31, 2020	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Sep. 30, 2019
Asset Impairments
Impairment losses							$ 206	$ 544	$ 75
Goodwill impairment losses		$ 130					130	35
Petra Nova Parish Holdings
Asset Impairments
Impairment losses on equity method investments						$ 18
Letter of credit										$ 12
East
Asset Impairments
Impairment losses	$ 43	$ 20	$ 16				13
Goodwill impairment losses							130	35
East \| Joliet facility
Asset Impairments
Impairment losses			213
East \| PJM Coal Generating Assets
Asset Impairments
Impairment losses				$ 271
Goodwill impairment losses				$ 35
West/Services/Other
Asset Impairments
Impairment losses			$ 9
West/Services/Other \| Held-for-sale \| Home Solar
Asset Impairments
Impairment loss to adjust the carrying amount of assets and liabilities					$ 29
West/Services/Other \| Cottonwood
Asset Impairments
Impairment losses on equity method investments									32
Texas
Asset Impairments
Goodwill impairment losses							$ 0	$ 0
Impairment losses, other assets									$ 14