Consolidated Entities and Equity Method Investments - Schedule of Equity Method Investments (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2022	Dec. 31, 2021
Schedule of Equity Method Investments [Line Items]
Investment Balance	$ 1,292	$ 1,282
SOUTHERN Co GAS
Schedule of Equity Method Investments [Line Items]
Investment Balance	1,125	1,173
SOUTHERN Co GAS | SNG
Schedule of Equity Method Investments [Line Items]
Investment Balance	1,091	1,129
SOUTHERN Co GAS | Other
Schedule of Equity Method Investments [Line Items]
Investment Balance	34	$ 44
SOUTHERN Co GAS | PennEast Pipeline
Schedule of Equity Method Investments [Line Items]
Distribution	$ 11