Effective Tax Rate and Unrecognized Tax Benefits - Narrative (Details)	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Effective Tax Rate and Unrecognized Tax Benefits (Textual) [Abstract]
Effective tax rate	33.90%	35.30%
Significantly increase or decrease in the amount of the unrecognized tax benefits associated with a majority of Southern	12 months
Alabama Power [Member]
Effective Tax Rate and Unrecognized Tax Benefits (Textual) [Abstract]
Effective tax rate	39.30%	38.80%
Georgia Power [Member]
Effective Tax Rate and Unrecognized Tax Benefits (Textual) [Abstract]
Effective tax rate	38.00%	35.80%
Gulf Power [Member]
Effective Tax Rate and Unrecognized Tax Benefits (Textual) [Abstract]
Effective tax rate	37.60%	37.30%
Mississippi Power [Member]
Effective Tax Rate and Unrecognized Tax Benefits (Textual) [Abstract]
Effective tax rate	(42.10%)	26.70%
Southern Power [Member]
Effective Tax Rate and Unrecognized Tax Benefits (Textual) [Abstract]
Effective tax rate	20.50%	34.40%