Statements of Common Stockholders' Equity - APC - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Alabama Power	Alabama Power Common Stock	Alabama Power Paid-In Capital	Alabama Power Retained Earnings	Alabama Power Accumulated Other Comprehensive Income (Loss)
Beginning balance (in shares) at Dec. 31, 2020		1,058					31
Beginning balance at Dec. 31, 2020						$ 9,810	$ 1,222	$ 5,413	$ 3,194	$ (19)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income after dividends on preferred stock	$ 2,393					1,238			1,238
Capital contributions from parent company						643		643
Other comprehensive income (loss)	158				$ 158	6				6
Cash dividends on common stock	(2,777)			$ (2,777)		(984)			(984)
Other	(7)		$ (8)	2
Ending balance (in shares) at Dec. 31, 2021		1,061					31
Ending balance at Dec. 31, 2021						10,713	$ 1,222	6,056	3,448	(13)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income after dividends on preferred stock	3,524					1,340			1,340
Capital contributions from parent company						654		654
Other comprehensive income (loss)	71				71	4				4
Cash dividends on common stock	(2,907)			(2,907)		(1,016)			(1,016)
Other	(6)		9	(8)	(1)	(8)			(8)
Ending balance (in shares) at Dec. 31, 2022		1,090					31
Ending balance at Dec. 31, 2022	30,408					11,687	$ 1,222	6,710	3,764	(9)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income after dividends on preferred stock	3,976					1,370			1,370
Capital contributions from parent company						415		415
Other comprehensive income (loss)	(10)				$ (10)	2				2
Cash dividends on common stock	(3,035)			(3,035)		(1,141)			(1,141)
Other	(5)		$ (1)	$ 3
Ending balance (in shares) at Dec. 31, 2023		1,092					31
Ending balance at Dec. 31, 2023	$ 31,444					$ 12,333	$ 1,222	$ 7,125	$ 3,993	$ (7)