Contingencies and Regulatory Matters (Details Textual) (USD $)	12 Months Ended		1 Months Ended		6 Months Ended	12 Months Ended		1 Months Ended			12 Months Ended									1 Months Ended		12 Months Ended											12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Jul. 31, 2007 Alabama Power [Member]	Jan. 31, 2001 Alabama Power [Member] Coal_Fired_Generating_Facilities	Jun. 30, 2011 Alabama Power [Member]	Dec. 31, 2011 Alabama Power [Member] Property Claims	Dec. 31, 2010 Alabama Power [Member] Claims	Apr. 30, 2008 Georgia Power [Member] MW	Jul. 31, 2007 Georgia Power [Member]	Jan. 31, 2001 Georgia Power [Member] Coal_Fired_Generating_Facilities	Dec. 31, 2011 Georgia Power [Member] MW Claims	Dec. 31, 2010 Georgia Power [Member]	Dec. 31, 2009 Georgia Power [Member]	Jun. 10, 2011 Georgia Power [Member]	Jun. 01, 2011 Georgia Power [Member]	Mar. 31, 2010 Georgia Power [Member]	Dec. 31, 2011 Georgia Power [Member] Plant Vogtle [Member]	Dec. 31, 2011 Gulf Power [Member]	Dec. 31, 2010 Gulf Power [Member]	May 31, 2010 Mississippi Power [Member] MW	May 31, 2009 Mississippi Power [Member]	Dec. 31, 2011 Mississippi Power [Member]	Dec. 31, 2008 Mississippi Power [Member]	Sep. 09, 2011 Mississippi Power [Member] mi	May 19, 2011 Mississippi Power [Member]	Apr. 27, 2011 Mississippi Power [Member]	Apr. 19, 2011 Mississippi Power [Member]	Mar. 04, 2011 Mississippi Power [Member]	Dec. 31, 2010 Mississippi Power [Member]	Aug. 19, 2010 Mississippi Power [Member]	Jul. 27, 2010 Mississippi Power [Member]	May 26, 2010 Mississippi Power [Member]	Dec. 31, 2011 Electricity Generation Plant, Non-Nuclear [Member] Mississippi Power [Member]	Dec. 31, 2011 Mine [Member] Mississippi Power [Member]
Contingencies and Regulatory Matters (Textual) [Abstract]
Number of coal fired generating facilities at which new source review violations occurred				5						3
Number of dismissed claims against Subsidiary							5
Total Number of Claims							8
Claims left for summary disposition or trial against Alabama Power							3
Environmental remediation liability											$ 17,000,000							$ 62,000,000
Civil penalties per violation rate											37,500
Number of times of punitive damages in comparison to cost incurred by Environmental Protection Agency											3
Claims awarded to companies related to nuclear fuel disposal litigation			17,000,000						30,000,000
Unrecognized tax benefits of additional tax benefits recorded														64,000,000
Related regulatory liability														62,000,000
Reduction in related interest expense														23,000,000
Anticipates of elimination adjustment will result in additional revenues						31,000,000
Maximum percentage of Rate RSE						4.00%
Maximum annual percentage of ratio rate						5.00%
Minimum projected retail return on common equity at which retail rates remain unchanged						13.00%
Maximum projected retail return on common equity at which retail rates remain unchanged						14.50%
Increase in amount of RSE							150,000,000
Maximum increase in rate RSE						5.00%
Under recovered certified PPA balance						6,000,000
Approximate Annual Reduction in CNP rate due to the expiration of the PPA						5,000,000	70,000,000
Increase in total annual billing based on fuel cost recovery rate approved by Georgia Power																373,000,000
Under recovered environmental clause						11,000,000
Approved billing rate under rate ECR up to (cents per KWH)						0.05910
Approximate increase in retail rates due to environmental costs for specified period							4.30%
Future stated rates of fuel cost recovery under rate ECR factor in terms of cents per KWH						0.02681
Maximum Period for recovery deferred storm-related operations and maintenance costs and any future reserve deficit						24 months
Deferred cost related to construction																						5,000,000
Grant funds receivable during construction																						245,000,000
Purchase of interest in plant																															17.50%
Portion of deferred construction cost under review																						46,000,000
Portion of actual earnings above approved ROE band refunded to customers											two-third
Portion of actual earnings above approved ROE band retained by Georgia Power											one-third
Estimated increase in ECCR tariff												168,000,000
Estimated increase in DSM tariffs												31,000,000
Estimated increase in tariff two in 2012											17,000,000
Estimated increase in tariff two in 2013											18,000,000
Increased traditional base tariffs to recover revenue in year one											122,000,000
Increased traditional base tariffs to recover revenue in year two											60,000,000
Set percentage of ROE under ARP											11.15%
Period over which deferred costs are being amortized to nuclear operations and maintenance expenses						18 months
Amortization of regulatory liability (up to one third) if Georgia Power does not file for retail base rate increase												216,000,000	108,000,000
Amount of regulatory liability amortized												174,000,000	41,000,000
Maximum projected retail ROE allowed to earn											10.25%
Maximum retail ROE allowed to earn												10.15%	9.75%
Reduction in projected in-service cost due to recovered cost											4,400,000,000
Nuclear outage operations and maintenance expenses decreased						50,000,000
Under recovered fuel cost						31,000,000	4,000,000
Nuclear outage expense	38,000,000
Number of units for which actual nuclear outage expenses deferred to regulatory asset account						1
Additional accruals of NDR charges reflected as operations and maintenance expense							48,000,000
Electric generating capacity in Mega Watts under consortium agreement								1,100
Plant capacity under coal gasification combined cycle technology in Mega Watts																				582
Recovery of project financing cost as per Legislation											1,700,000,000
Expected remaining regulatory liability to be amortized in next two years											92,000,000
Retail ROE, Minimum											10.25%
Base Revenue under Alternate Base Plan												562,000,000
Increase in traditional base tariff rates												347,000,000
Total certified cost											6,100,000,000
Under recovered fuel balance											137,000,000
Authorized limit under NDR reserve							75,000,000
Number of days required by Georgia PSC to implement Interim Cost Recovery Tariff											90 days
Increase in Municipal Franchise Fee tariff rates												16,000,000
Adjustment to fuel cost recovery rate if under recovered fuel balance exceeds budget											75,000,000
Accumulated NDR reserve reflected as other regulatory liabilities, deferred						110,000,000	127,000,000
Accumulated NDR reserve reflected as other regulatory liabilities, deferred							75,000,000
Amount of government construction cost incentive received																																296,000,000
Percentage of proportionate share owed in Consortium Agreement											45.70%
Maximum cap construction cost																						2,880,000,000
Finance cost to be recovered Annually																										98,000,000
Increase in rate to recover finance cost																										11.66%
Term of management fee contract with liberty fuels company																																		40 years
Estimated cost associated with repairing damage facility to operation and maintenance expenses					42,000,000
Retail ROE, Maximum											12.25%
Estimated cost associated with repairing damage facility to capital expenditure					161,000,000
Estimated cost																																	2,400,000,000
Percentage of financing costs of construction work in progress																																100.00%
Number of units for which outage operations and maintenance expenses accrued						2
Cost deferred in other regulatory assets	3,532,000,000	2,402,000,000				994,000,000	675,000,000				1,604,000,000	1,207,000,000						323,116,000	219,877,000			185,694,000							132,420,000
Other deferred charges and assets	481,000,000	436,000,000				186,000,000	196,000,000				187,000,000	207,000,000						39,493,000	34,936,000			28,674,000							33,233,000
Refunds related to earnings											0
Capacity of units used by Georgia Power to control fuel switch or retire remaining fossil generating units where environmental controls not yet install											2,600
Capacity of units used by Georgia Power more likely than others to switch fuel or control in time to comply with utility MACT Rule											600
Currently available capacity of unit not rely by Georgia Power in 2015											2,000
Capacity of units include application request by Georgia Power that country PSC certify purchase from four PPAs selected through 2015 request for proposal process											1,562
Additional contractual obligations, 2015											84,000,000
Additional contractual obligations, 2016											102,000,000
Additional contractual obligations, 2017 and thereafter											1,400,000,000
Certain wholesale capacity scheduled to return to retail service in future period											562
Expected decrease in annual billings for fuel costs															43,000,000
Cost deferred in other regulatory assets																						21,000,000
Previously expensed																						1,000,000
Amortization to earnings of financing costs capitalized over the five year period											91,000,000
Costs included in CWIP											73,000,000						1,900,000,000					918,000,000
Percentage increase in certified amount for project											3.90%
Regulatory liability for state income tax credits to be amortized											62,000,000
Regulatory liability for state income tax credits amortization period											21 months
Tax credits (Phase I)																					133,000,000
Tax credits (Phase II)																											279,000,000
Minimum percentage of carbon dioxide that must be capture and sequester to remain eligible for the phase II tax credits																						65.00%
Accrued tax benefits on tax credits																						100,000,000
The percentage of bonus tax depreciation on certain placed, or to be placed assets																						100.00%
Tax credits not available for use until future period																						77,000,000
Agreement reached to assign the remaining funds to the Kemper IGCC																							270,000,000
Grant funds assigned to receive during initial operations of plant																														25,000,000
Percentage of Carbon dioxide captured from project by purchase Denbury																												70.00%
Percentage of contract to purchase carbon dioxide from Kemper IGCC																									30.00%
New Co2 Pipeline Infrastructure																								61
Estimated cost of pipeline infrastructure																								141,000,000
Estimated capital cost of mine																						245,000,000
Cost incurred by Mississippi Power associated with plant including regulatory filing costs																						943,000,000
Costs associated with CCP12 grant funds																						245,000,000
Other deferred charges and assets																						3,000,000
Contingencies and Regulatory Matters (Additional Textual) [Abstract]
Civil penalties under Clean Air Act per day, lower range	25,000
Civil penalties under Clean Air Act per day, upper range	37,500
Damages from lost property values and relocating village cost, lower range	95,000,000
Damages from lost property values and relocating village cost, upper range	$ 400,000,000