Segment and Related Information (Details) (USD $)	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011	Dec. 31, 2011
Financial data for business segments
Operating revenues	$ 3,604,000,000	$ 4,012,000,000
Consolidated Net Income After Dividends on Preferred and Preference Stock of Subsidiaries	368,000,000	422,000,000
Total Assets	59,874,000,000		59,267,000,000
Electric Utilities [Member]
Financial data for business segments
Operating revenues	3,589,000,000	3,994,000,000
Consolidated Net Income After Dividends on Preferred and Preference Stock of Subsidiaries	369,000,000	423,000,000
Total Assets	59,213,000,000		58,076,000,000
Traditional Operating Companies [Member] | Electric Utilities [Member]
Financial data for business segments
Operating revenues	3,449,000,000	3,810,000,000
Consolidated Net Income After Dividends on Preferred and Preference Stock of Subsidiaries	339,000,000	385,000,000
Total Assets	55,698,000,000		54,622,000,000
Southern Power [Member]
Segment and Related Information (Textual) [Abstract]
Southern Power's revenues from sales to the traditional operating companies	112,000,000	83,000,000
Southern Power [Member] | Electric Utilities [Member]
Financial data for business segments
Operating revenues	254,000,000	282,000,000
Consolidated Net Income After Dividends on Preferred and Preference Stock of Subsidiaries	29,000,000	38,000,000
Total Assets	3,596,000,000		3,581,000,000
Eliminations [Member] | Electric Utilities [Member]
Financial data for business segments
Operating revenues	(114,000,000)	(98,000,000)
Consolidated Net Income After Dividends on Preferred and Preference Stock of Subsidiaries	1,000,000
Total Assets	(81,000,000)		(127,000,000)
All Other [Member]
Financial data for business segments
Operating revenues	38,000,000	38,000,000
Consolidated Net Income After Dividends on Preferred and Preference Stock of Subsidiaries	2,000,000	1,000,000
Total Assets	1,086,000,000		1,592,000,000
Eliminations [Member]
Financial data for business segments
Operating revenues	(23,000,000)	(20,000,000)
Consolidated Net Income After Dividends on Preferred and Preference Stock of Subsidiaries	(3,000,000)	(2,000,000)
Total Assets	$ (425,000,000)		$ (401,000,000)