Consolidated Statements of Stockholders' Equity - Southern - USD ($) shares in Millions, $ in Millions		Total	Common Stock	Treasury	Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interests
Beginning balance (in shares) at Dec. 31, 2018			1,035	1
Beginning balance at Dec. 31, 2018		$ 29,039	$ 5,164	$ (38)	$ 11,094	$ 8,706	$ (203)	$ 4,316
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Consolidated net income (loss)		4,729				4,739		(10)
Other comprehensive income (loss)		(118)					(118)
Issuance of equity units	[1]	(198)			(198)
Stock issued (in shares)			19
Stock issued		844	$ 93		751
Stock-based compensation		66			66
Cash dividends on common stock		(2,570)				(2,570)
Contributions from noncontrolling interests		276						276
Distributions to noncontrolling interests		(327)						(327)
Other		18		$ (4)	21	2		(1)
Ending balance (in shares) at Dec. 31, 2019			1,054	1
Ending balance at Dec. 31, 2019		31,759	$ 5,257	$ (42)	11,734	10,877	(321)	4,254
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Consolidated net income (loss)		3,088				3,119		(31)
Other comprehensive income (loss)		(75)					(75)
Stock issued (in shares)			4
Stock issued		74	$ 11		63
Stock-based compensation		44			44
Cash dividends on common stock		(2,685)				(2,685)
Contributions from noncontrolling interests		307						307
Distributions to noncontrolling interests		(271)						(271)
Purchase of membership interests from noncontrolling interests					5
Purchase of membership interests from noncontrolling interests		(60)						(65)
Sale of noncontrolling interests		65			(2)			67
Other		(12)		$ (4)	(10)		1	1
Ending balance (in shares) at Dec. 31, 2020			1,058	1
Ending 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)		2,294				2,393		(99)
Other comprehensive income (loss)		158					158
Stock issued (in shares)			3
Stock issued		73	$ 11		62
Stock-based compensation		62			62
Cash dividends on common stock		(2,777)				(2,777)
Contributions from noncontrolling interests		590						590
Distributions to noncontrolling interests		(351)						(351)
Other		(7)		$ (1)	(8)	2
Ending balance (in shares) at Dec. 31, 2021			1,061	1
Ending balance at Dec. 31, 2021		$ 32,276	$ 5,279	$ (47)	$ 11,950	$ 10,929	$ (237)	$ 4,402

[1] See Note 8 under "Equity Units" for additional information.