Dispositions - Narrative (Details)	3 Months Ended		12 Months Ended
	Mar. 31, 2024 USD ($) MWh project	Mar. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)	Mar. 01, 2023 USD ($) project	Oct. 01, 2022 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Period to obtain consent (in years)	2 years
Number of solar projects | project	2
Clean Energy Businesses | RWE | Maximum
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Estimate of possible loss (up to)	$ 172,000,000
Disposal Group, Held-for-sale, Not Discontinued Operations | Clean Energy Businesses
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration from sale of business				$ 3,993,000,000	$ 6,800,000,000
Gain on sale of subsidiary	835,000,000	$ 855,000,000	$ 865,000,000
Gain on sale of subsidiary, after tax	745,000,000	791,000,000	767,000,000
Downward price adjustment	30,000,000
Downward price adjustment, after tax	$ 22,000,000
Tax equity projects | project	3			2
Transaction costs, before tax	$ 0	11,000,000
Transaction costs, after tax		$ 8,000,000
Depreciation and amortization, before tax			41,000,000
Depreciation and amortization, after tax			$ 28,000,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations | Crane Project
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Holding period (in years)	5 years
Carrying value of tax equity interest	$ 7,000,000
Electric Energy (MWh)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Notional amount | MWh	31,374,625
Broken Bow II | Electric Energy (MWh) | Clean Energy Businesses
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Deferred projects | project	1			1
Notional amount | MWh	75