Consolidated Statements of Comprehensive Income (Parenthetical) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Changes in fair value of qualifying hedges, tax	$ 0	$ (7,000,000)	$ (10,000,000)
Reclassification adjustment for amounts of qualifying hedges included in net income, tax	5,000,000	7,000,000	6,000,000
Change in fair value of marketable securities, tax	(2,000,000)	0	(2,000,000)
Benefit plan net gain (loss), tax	22,000,000	(2,000,000)	(1,000,000)
Reclassification adjustment for amounts of pension and other post retirement benefit plans included in net income, tax	4,000,000	(4,000,000)	(14,000,000)
Alabama Power [Member]
Changes in fair value of qualifying hedges, tax	0	(7,000,000)	(5,000,000)
Reclassification adjustment for amounts of qualifying hedges included in net income, tax	1,000,000	1,000,000	(1,000,000)
Georgia Power [Member]
Reclassification adjustment for amounts of qualifying hedges included in net income, tax	1,000,000	1,000,000	2,000,000
Gulf Power [Member]
Reclassification adjustment for amounts of qualifying hedges included in net income, tax	297,000	360,000	360,000
Mississippi Power [Member]
Changes in fair value of qualifying hedges, tax	0	(296,000)	(5,494,000)
Reclassification adjustment for amounts of qualifying hedges included in net income, tax	526,000	411,000	(18,000)
Southern Power [Member]
Changes in fair value of qualifying hedges, tax	0	(90,000)	55,000
Reclassification adjustment for amounts of qualifying hedges included in net income, tax	$ 2,357,000	$ 3,919,000	$ 4,837,000