Effective Tax Rate - Narrative (Details)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Effective Tax Rate and Unrecognized Tax Benefits (Textual) [Abstract]
Effective tax rate	32.30%	24.50%
Alabama Power [Member]
Effective Tax Rate and Unrecognized Tax Benefits (Textual) [Abstract]
Effective tax rate	39.30%	39.20%
Georgia Power [Member]
Effective Tax Rate and Unrecognized Tax Benefits (Textual) [Abstract]
Effective tax rate	38.00%	38.10%
Gulf Power [Member]
Effective Tax Rate and Unrecognized Tax Benefits (Textual) [Abstract]
Effective tax rate	37.40%	37.60%
Mississippi Power [Member]
Effective Tax Rate and Unrecognized Tax Benefits (Textual) [Abstract]
Effective tax rate	(43.00%)	(40.80%)
Southern Power [Member]
Effective Tax Rate and Unrecognized Tax Benefits (Textual) [Abstract]
Effective tax rate	8.50%	33.50%