Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - Southern - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Treasury	Paid-In Capital	Retained Earnings (Accumulated Deficit)	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interests
Beginning balance (in shares) at Dec. 31, 2020		1,058	1
Beginning balance at Dec. 31, 2020	$ 32,234	$ 5,268	$ (46)	$ 11,834	$ 11,311	$ (395)	$ 4,262
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Consolidated net income (loss)	1,103				1,135		(32)
Other comprehensive income (loss)	28					28
Stock issued (in shares)		2
Stock issued	14	$ 5		9
Stock-based compensation	9			9
Cash dividends on common stock	(678)				(678)
Capital contributions from noncontrolling interests	403						403
Distributions to noncontrolling interests	(46)						(46)
Other	1			2			(1)
Ending balance (in shares) at Mar. 31, 2021		1,060	1
Ending balance at Mar. 31, 2021	33,068	$ 5,273	$ (46)	11,854	11,768	(367)	4,586
Beginning balance (in shares) at Dec. 31, 2021		1,061	1
Beginning balance at Dec. 31, 2021	32,276	$ 5,279	$ (47)	11,950	10,929	(237)	4,402
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Consolidated net income (loss)	987				1,032		(45)
Other comprehensive income (loss)	42					42
Stock issued (in shares)		3
Stock issued	38	$ 7		31
Stock-based compensation	6			6
Cash dividends on common stock	(702)				(702)
Capital contributions from noncontrolling interests	73						73
Distributions to noncontrolling interests	(98)						(98)
Other	7		$ (2)	7	2
Ending balance (in shares) at Mar. 31, 2022		1,064	1
Ending balance at Mar. 31, 2022	$ 32,629	$ 5,286	$ (49)	$ 11,994	$ 11,261	$ (195)	$ 4,332