Deferred gains and losses amortized into earnings.

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Energy-related derivative contracts for the registrants.

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Fair value gain (Loss).

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Fair value gain loss foreign currency derivatives.

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Longest hedge date.

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Longest Non-Hedge date.

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Net quantity Purchase of derivatives not designated as hedges.

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Net quantity sold of derivatives not designated as hedges.

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Notional amount of interest rate derivatives, interest rate paid.

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Notional amount of interest rate derivatives, interest rate received.

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The contractual rate at which a foreign currency can be purchased or sold under the terms of a foreign currency derivative contract.

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Description of the transactions or other events that will result in the reclassification into earnings of gains or losses reported in accumulated other comprehensive income. Includes time period over which gains or losses will be reclassified to earnings.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 45

-Subparagraph b(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

-Paragraph 1

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The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Date when foreign currency exchange rate derivatives mature or expire.

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Aggregate notional amount of all derivatives designated as cash flow hedging instruments. The notional amount relates to a number of currency units, shares, bushels, pounds, or other units specified in a derivative instrument.

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-Name Accounting Standards Codification

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Aggregate notional amount of all derivatives designated as a fair value hedging instrument. The notional amount relates to a number of currency units, shares, bushels, pounds, or other units specified in a derivative instrument.

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Derivatives (Details) In Millions, unless otherwise specified	9 Months Ended					9 Months Ended		9 Months Ended		9 Months Ended										9 Months Ended
	Sep. 30, 2011 USD ($)	Sep. 30, 2011 Alabama Power [Member] USD ($)	Sep. 30, 2011 Alabama Power [Member] Gas [Member] Million_British_Thermal_Unit	Sep. 30, 2011 Alabama Power [Member] Cash Flow Hedging [Member] Interest Rate Contract Two [Member] USD ($)	Sep. 30, 2011 Alabama Power [Member] Interest Rate Contract Two [Member] USD ($)	Sep. 30, 2011 Georgia Power [Member] USD ($)	Sep. 30, 2011 Georgia Power [Member] Gas [Member] Million_British_Thermal_Unit	Sep. 30, 2011 Gulf Power [Member] USD ($)	Sep. 30, 2011 Gulf Power [Member] Gas [Member] Million_British_Thermal_Unit	Sep. 30, 2011 Mississippi Power [Member] USD ($)	Sep. 30, 2011 Mississippi Power [Member] Gas [Member] Million_British_Thermal_Unit	Sep. 30, 2011 Mississippi Power [Member] Cash Flow Hedging [Member] Interest Rate Contract Three [Member] USD ($)	Sep. 30, 2011 Mississippi Power [Member] Cash Flow Hedging [Member] Interest Rate Contract Four [Member]	Sep. 30, 2011 Mississippi Power [Member] Cash Flow Hedging [Member] Interest Rate Contract Five [Member] USD ($)	Sep. 30, 2011 Mississippi Power [Member] Fair Value Hedging [Member] USD ($)	Sep. 30, 2011 Mississippi Power [Member] Fair Value Hedging [Member] EUR (€)	Sep. 30, 2011 Mississippi Power [Member] Interest Rate Contract Three [Member] USD ($)	Sep. 30, 2011 Mississippi Power [Member] Interest Rate Contract Four [Member] USD ($)	Sep. 30, 2011 Mississippi Power [Member] Interest Rate Contract Five [Member] USD ($)	Sep. 30, 2011 Southern Power [Member] USD ($)	Sep. 30, 2011 Southern Power [Member] Power [Member] Megawatt	Sep. 30, 2011 Southern Power [Member] Gas [Member] Million_British_Thermal_Unit	Sep. 30, 2011 Power [Member] Megawatt	Sep. 30, 2011 Gas [Member] Million_British_Thermal_Unit	Sep. 30, 2011 Cash Flow Hedging [Member] Interest Rate Contract One [Member] USD ($)	Sep. 30, 2011 Fair Value Hedging [Member] USD ($)	Sep. 30, 2011 Interest Rate Contract One [Member] USD ($)
Energy-related derivative contracts
Net Sold MWHs																					300,000		300,000
Net Purchased mmBtu			31,000,000				66,000,000		26,000,000		31,000,000											7,000,000		160,000,000
Longest Hedge Date			2015				2015		2015		2015											2012		2015
Longest Non-Hedge Date																					2011	2015	2011	2015
Notional amount of interest rate derivatives
Notional Amount, Fair Value	$ 350
Notional Amount					300												150	150	300								300
Notional Amount of interest rate derivatives, Total	1,550
Interest Rate Received				3-month LIBOR								3-month LIBOR	3-month LIBOR	3-month LIBOR											3-month LIBOR + 0.40% spread	0.0415
Interest Rate Paid				0.0290								0.0237	0.0125	0.0266											0.0124	3-month LIBOR + 1.96%* spread
Hedge Maturity Date				Dec. 01, 2022								Sep. 01, 2021	Sep. 01, 2016	Apr. 01, 2022											Oct. 01, 2011	May 01, 2014
Fair Value Gain (Loss) September 30, 2011	(11)			(12)								(4)		(11)											0	16
Total deferred gains and losses are expected to be amortized into earnings
Estimated Gain (Loss) to be Reclassified for the 12 Months Ending September 30, 2012	(16)	0				(3)		(1)		(1)										(11)
Total Deferred Gains (Losses) Amortized Through	2037	2035				2037		2020		2022										2016
Notional amount of foreign currency derivatives
Notional Amount																28.3
Average Forward Rate															1.297	1.297
Hedge Maturity Date															Various through March 2014	Various through March 2014
Fair Value Gain (Loss) September 30, 2011															$ 1