Joint Ownership Agreements (Details) (USD $)	12 Months Ended
	Dec. 31, 2013 MW		Dec. 31, 2012	Dec. 31, 2011
Jointly owned utility plant interests
Plant acquisition adjustment	$ 123,000,000		$ 124,000,000
Plant Vogtle (nuclear) Units 1 and 2 [Member]
Jointly owned utility plant interests
Percent Ownership	45.70%
Plant in Service	3,375,000,000
Accumulated Depreciation	2,028,000,000
Construction Work in Progress	0
Plant Hatch (nuclear) [Member]
Jointly owned utility plant interests
Percent Ownership	50.10%
Plant in Service	1,092,000,000
Accumulated Depreciation	551,000,000
Construction Work in Progress	0
Plant Miller (coal) Units 1 and 2 [Member]
Jointly owned utility plant interests
Percent Ownership	91.80%
Plant in Service	1,410,000,000
Accumulated Depreciation	575,000,000
Construction Work in Progress	0
Plant Scherer (coal) Units 1 and 2 [Member]
Jointly owned utility plant interests
Percent Ownership	8.40%
Plant in Service	209,000,000
Accumulated Depreciation	80,000,000
Construction Work in Progress	0
Plant Wansley (coal) [Member]
Jointly owned utility plant interests
Percent Ownership	53.50%
Plant in Service	800,000,000
Accumulated Depreciation	260,000,000
Construction Work in Progress	0
Rocky Mountain (pumped storage) [Member]
Jointly owned utility plant interests
Percent Ownership	25.40%
Plant in Service	182,000,000
Accumulated Depreciation	120,000,000
Construction Work in Progress	0
Intercession City (combustion turbine) [Member]
Jointly owned utility plant interests
Percent Ownership	33.30%
Plant in Service	14,000,000
Accumulated Depreciation	4,000,000
Construction Work in Progress	0
Plant Stanton (combined cycle) Unit A [Member]
Jointly owned utility plant interests
Percent Ownership	65.00%
Plant in Service	156,000,000
Accumulated Depreciation	42,000,000
Construction Work in Progress	0
Alabama Power [Member]
Jointly owned utility plant interests
Total Megawatt Capacity	1,000
Percent Ownership	14.00%
Plant acquisition adjustment	12,000,000		12,000,000
Joint Ownership Agreements (Textual) [Abstract]
Jointly Owned Affiliate Equity	84,000,000
Jointly Owned Affiliate Long Term Debt	125,000,000
Jointly Owned Affiliate Long Term Debt Annual Interest Requirement	3,000,000
Dividends paid by equity method investment	7,000,000		14,000,000	15,000,000
Ownership percentage, equity method investment	50.00%
Alabama Power [Member] | SEGCO [Member]
Jointly owned utility plant interests
Total Megawatt Capacity	1,020
Joint Ownership Agreements (Textual) [Abstract]
Share Of Purchased Power	88,000,000		109,000,000	142,000,000
Unconditional guarantee to pay outstanding pollution control revenue bond principal	25,000,000
Guarantee of unsecured senior notes	50,000,000
Alabama Power [Member] | Senior notes due December 1, 2018 [Member] | SEGCO [Member]
Joint Ownership Agreements (Textual) [Abstract]
Guarantee of unsecured senior notes	100,000,000
Alabama Power [Member] | Natural Gas Pipeline [Member]
Jointly owned utility plant interests
Construction Work in Progress	1,000,000
Alabama Power [Member] | Plant Miller (coal) Units 1 and 2 [Member]
Jointly owned utility plant interests
Total Megawatt Capacity	1,320
Percent Ownership	91.84%	[1]
Plant in Service	1,410,000,000
Accumulated Depreciation	575,000,000
Construction Work in Progress	89,000,000
Alabama Power [Member] | SEGCO [Member]
Jointly owned utility plant interests
Percent Ownership	86.00%
Alabama Power [Member] | Greene County [Member]
Jointly owned utility plant interests
Total Megawatt Capacity	500
Percent Ownership	60.00%	[2]
Plant in Service	157,000,000
Accumulated Depreciation	91,000,000
Construction Work in Progress	5,000,000
Georgia Power [Member]
Jointly owned utility plant interests
Plant acquisition adjustment	28,000,000		28,000,000
Georgia Power [Member] | SEGCO [Member]
Joint Ownership Agreements (Textual) [Abstract]
Share Of Purchased Power	91,000,000		107,000,000
Georgia Power [Member] | Purchased Power from Affiliates [Member] | SEGCO [Member]
Joint Ownership Agreements (Textual) [Abstract]
Share Of Purchased Power				141,000,000
Georgia Power [Member] | Alabama Power [Member]
Jointly owned utility plant interests
Total Megawatt Capacity	1,020
Georgia Power [Member] | Plant Vogtle (nuclear) Units 1 and 2 [Member]
Jointly owned utility plant interests
Percent Ownership	45.70%
Plant in Service	3,375,000,000
Accumulated Depreciation	2,028,000,000
Construction Work in Progress	53,000,000
Georgia Power [Member] | Plant Hatch (nuclear) [Member]
Jointly owned utility plant interests
Percent Ownership	50.10%
Plant in Service	1,092,000,000
Accumulated Depreciation	551,000,000
Construction Work in Progress	52,000,000
Georgia Power [Member] | Plant Scherer (coal) Units 1 and 2 [Member]
Jointly owned utility plant interests
Percent Ownership	8.40%
Plant in Service	209,000,000
Accumulated Depreciation	80,000,000
Construction Work in Progress	24,000,000
Georgia Power [Member] | Plant Wansley (coal) [Member]
Jointly owned utility plant interests
Percent Ownership	53.50%
Plant in Service	800,000,000
Accumulated Depreciation	260,000,000
Construction Work in Progress	36,000,000
Georgia Power [Member] | Rocky Mountain (pumped storage) [Member]
Jointly owned utility plant interests
Percent Ownership	25.40%
Plant in Service	182,000,000
Accumulated Depreciation	120,000,000
Construction Work in Progress	0
Georgia Power [Member] | Intercession City (combustion turbine) [Member]
Jointly owned utility plant interests
Percent Ownership	33.30%
Plant in Service	14,000,000
Accumulated Depreciation	4,000,000
Construction Work in Progress	0
Georgia Power [Member] | Vogtle Units 3 and 4 [Member]
Jointly owned utility plant interests
Percent Ownership	45.70%
Georgia Power [Member] | Plant Scherer Unit 3 (coal) [Member]
Jointly owned utility plant interests
Percent Ownership	75.00%
Plant in Service	1,155,000,000
Accumulated Depreciation	398,000,000
Construction Work in Progress	19,000,000
Gulf Power [Member]
Jointly owned utility plant interests
Plant acquisition adjustment	2,031,000		2,286,000
Gulf Power [Member] | Plant Scherer Unit 3 (coal) [Member]
Jointly owned utility plant interests
Total Megawatt Capacity	818
Percent Ownership	25.00%
Plant in Service	382,374,000	[3]
Accumulated Depreciation	123,862,000
Construction Work in Progress	6,303,000
Plant acquisition adjustment	2,000,000
Gulf Power [Member] | Plant Daniel Units 1 &2 2 [Member]
Jointly owned utility plant interests
Total Megawatt Capacity	1,000
Percent Ownership	50.00%
Plant in Service	282,370,000
Accumulated Depreciation	172,365,000
Construction Work in Progress	169,085,000
Mississippi Power [Member]
Jointly owned utility plant interests
Plant acquisition adjustment	81,412,000		81,412,000
Mississippi Power [Member] | Greene County [Member] | Alabama Power [Member]
Jointly owned utility plant interests
Total Megawatt Capacity	500
Percent Ownership	40.00%
Plant in Service	96,153,000
Accumulated Depreciation	49,731,000
Construction Work in Progress	3,017,000
Mississippi Power [Member] | Plant Daniel Units 1 &2 2 [Member]
Jointly owned utility plant interests
Percent Ownership	50.00%
Mississippi Power [Member] | Plant Daniel Units 1 &2 2 [Member] | Gulf Power [Member]
Jointly owned utility plant interests
Total Megawatt Capacity	1,000
Percent Ownership	50.00%
Plant in Service	299,179,000
Accumulated Depreciation	152,952,000
Construction Work in Progress	168,539,000
Southern Power [Member]
Jointly owned utility plant interests
Total Megawatt Capacity	659
Southern Power [Member] | Plant Stanton (combined cycle) Unit A [Member]
Jointly owned utility plant interests
Plant in Service	156,000,000
Accumulated Depreciation	$ 41,800,000
Southern Power [Member] | Plant Stanton (combined cycle) Unit A [Member] | Southern Power [Member]
Jointly owned utility plant interests
Percent Ownership	65.00%
Southern Power [Member] | Plant Stanton (combined cycle) Unit A [Member] | Orlando Utilities Commission [Member]
Jointly owned utility plant interests
Percent Ownership	28.00%
Southern Power [Member] | Plant Stanton (combined cycle) Unit A [Member] | Florida Municipal Power Agency [Member]
Jointly owned utility plant interests
Percent Ownership	3.50%
Southern Power [Member] | Plant Stanton (combined cycle) Unit A [Member] | Kissimmee Utility Authority [Member]
Jointly owned utility plant interests
Percent Ownership	3.50%

[1] Jointly owned with PowerSouth Energy Cooperative, Inc.

[2] Jointly owned with an affiliate, Mississippi Power.

[3] Includes net plant acquisition adjustment of $2.0 million.