Consolidated Statements of Comprehensive Income (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net Income (Loss)	$ 2,031,000,000	$ 1,710,000,000	$ 2,415,000,000
Qualifying hedges:
Changes in fair value, net of tax	(10,000,000)	0	(12,000,000)
Reclassification adjustment for amounts included in net income, net of tax	5,000,000	9,000,000	11,000,000
Marketable securities:
Change in fair value, net of tax	0	(3,000,000)	0
Pension and other postretirement benefit plans:
Benefit plan net gain (loss),net of tax	(51,000,000)	36,000,000	(3,000,000)
Reclassification adjustment for amounts included in net income, net of tax	3,000,000	6,000,000	(8,000,000)
Total other comprehensive income (loss)	(53,000,000)	48,000,000	(12,000,000)
Dividends on Preferred and Preference Stock	68,000,000	66,000,000	65,000,000
Comprehensive Income	1,910,000,000	1,692,000,000	2,338,000,000
Alabama Power [Member]
Net Income (Loss)	800,000,000	751,000,000	743,000,000
Qualifying hedges:
Changes in fair value, net of tax	(5,000,000)	0	(11,000,000)
Reclassification adjustment for amounts included in net income, net of tax	2,000,000	1,000,000	2,000,000
Pension and other postretirement benefit plans:
Total other comprehensive income (loss)	(3,000,000)	1,000,000	(9,000,000)
Dividends on Preferred and Preference Stock	39,000,000	39,000,000	39,000,000
Comprehensive Income	797,000,000	752,000,000	734,000,000
Georgia Power [Member]
Net Income (Loss)	1,242,000,000	1,191,000,000	1,185,000,000
Qualifying hedges:
Changes in fair value, net of tax	(5,000,000)	0	0
Reclassification adjustment for amounts included in net income, net of tax	2,000,000	2,000,000	2,000,000
Pension and other postretirement benefit plans:
Total other comprehensive income (loss)	(3,000,000)	2,000,000	2,000,000
Dividends on Preferred and Preference Stock	17,000,000	17,000,000	17,000,000
Comprehensive Income	1,239,000,000	1,193,000,000	1,187,000,000
Gulf Power [Member]
Net Income (Loss)	149,179,000	132,133,000	132,135,000
Qualifying hedges:
Reclassification adjustment for amounts included in net income, net of tax	372,000	472,000	573,000
Pension and other postretirement benefit plans:
Total other comprehensive income (loss)	372,000	472,000	573,000
Dividends on Preferred and Preference Stock	9,003,000	7,704,000	6,203,000
Comprehensive Income	149,551,000	132,605,000	132,708,000
Mississippi Power [Member]
Net Income (Loss)	(326,948,000)	(474,892,000)	101,675,000
Qualifying hedges:
Changes in fair value, net of tax	0	0	(479,000)
Reclassification adjustment for amounts included in net income, net of tax	849,000	849,000	663,000
Pension and other postretirement benefit plans:
Total other comprehensive income (loss)	849,000	849,000	184,000
Dividends on Preferred and Preference Stock	1,733,000	1,733,000	1,733,000
Comprehensive Income	(326,099,000)	(474,043,000)	101,859,000
Southern Power [Member]
Net Income (Loss)	175,075,000	165,533,000	175,285,000
Qualifying hedges:
Changes in fair value, net of tax	0	0	(136,000)
Reclassification adjustment for amounts included in net income, net of tax	367,000	3,695,000	6,189,000
Pension and other postretirement benefit plans:
Total other comprehensive income (loss)	367,000	3,695,000	6,053,000
Less: Comprehensive income attributable to noncontrolling interests	2,775,000	0	0
Comprehensive Income	$ 172,667,000	$ 169,228,000	$ 181,338,000