Condensed Consolidated Statements of Comprehensive Income (Unaudited) (Parenthetical) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Qualifying hedges:
Changes in fair value of qualifying hedges, tax	$ (10,000,000)		$ (8,000,000)
Reclassification adjustment for amounts of qualifying hedges included in net income, tax	2,000,000	4,000,000	4,000,000	10,000,000
Marketable securities:
Change in fair value of marketable securities, tax	(2,000,000)		(1,000,000)
Pension and other post retirement benefit plans:
Reclassification adjustment for amounts of pension and other post retirement benefit plans included in net income, tax	2,000,000	1,000,000	2,000,000	1,000,000
Alabama Power [Member]
Qualifying hedges:
Changes in fair value of qualifying hedges, tax	(4,000,000)		(3,000,000)
Reclassification adjustment for amounts of qualifying hedges included in net income, tax			(1,000,000)
Georgia Power [Member]
Qualifying hedges:
Reclassification adjustment for amounts of qualifying hedges included in net income, tax		1,000,000	1,000,000	5,000,000
Gulf Power [Member]
Qualifying hedges:
Changes in fair value of qualifying hedges, tax				(542,000)
Reclassification adjustment for amounts of qualifying hedges included in net income, tax	90,000	90,000	270,000	286,000
Mississippi Power [Member]
Qualifying hedges:
Changes in fair value of qualifying hedges, tax	(5,630,000)	4,000	(5,624,000)	8,000
Southern Power [Member]
Qualifying hedges:
Changes in fair value of qualifying hedges, tax	(135,000)	1,125,000	265,000	1,536,000
Reclassification adjustment for amounts of qualifying hedges included in net income, tax	$ 1,106,000	$ 1,018,000	$ 3,261,000	$ 3,011,000