Acquisitions and Dispositions - Southern Power Narrative (Details) - SOUTHERN POWER CO - MW	1 Months Ended		3 Months Ended	12 Months Ended
	Mar. 31, 2022	Feb. 28, 2022	Mar. 31, 2022	Dec. 31, 2021
Tranquillity Solar Storage
Business Acquisition [Line Items]
Nameplate capacity placed in service (in MWs)	40		40	32
Garland Solar Storage
Business Acquisition [Line Items]
Nameplate capacity placed in service (in MWs)		15	15	73