2.2.0.25truefalse06063 - Disclosure - Financing (Details Textual)truefalsefalse1falsefalseUSDfalsefalse1/1/2010 - 12/31/2010 USD ($) USD ($) / shares $Jan-01-2010_Dec-31-2010http://www.sec.gov/CIK0000092122duration2010-01-01T00:00:002010-12-31T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170PureStandardhttp://www.xbrl.org/2003/instancepurexbrli0USDEPSDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0SharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0USDUSD$2falsefalseUSDfalsefalse1/1/2009 - 12/31/2009 USD ($) USD ($) / shares $TwelveMonthsEnded_31Dec2009http://www.sec.gov/CIK0000092122duration2009-01-01T00:00:002009-12-31T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170PureStandardhttp://www.xbrl.org/2003/instancepurexbrli0SharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0USDEPSDividehttp://www.xbrl.org/2003/iso4217USDiso4217http://www.xbrl.org/2003/instancesharesxbrli0USDUSD$2true0us-gaap_InvestmentHoldingsLineItemsus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringLine items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.falsefalseInvestment Holdings [Line Items]3false0us-gaap_ShortTermBankLoansAndNotesPayableus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse10000001000000falsetruefalsefalsefalse2truefalsefalse00falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryCarrying amount at the balance sheet date of borrowings from a bank, not elsewhere enumerated in the taxonomy, with a maturity within one year (or within one operating cycle if longer) from the date of borrowing.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Subparagraph a -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 7 falsefalseAmount short term bank loans4false0us-gaap_SeniorNotesus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse1520000000015200000000falsefalsefalsefalsefalse2truefalsefalse1470000000014700000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryIncluding the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 falsefalseSenior notes outstanding5false0us-gaap_LongtermPollutionControlBondCurrentAndNoncurrentus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse31000000003100000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryRepresents the current and noncurrent portions of a debt security issued by a state, certain agencies or authorities, a local government, or development corporation to finance the construction of air- or water-pollution control facilities or sewage or solid waste disposal facilities pursuant to federal law. The bonds are backed by the credit of the beneficiary of the financing rather than the credit of the issuer. New issues of these bonds are prohibited under the 1986 Tax Law.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20, 22 -Article 5 falsefalsePollution control revenue bonds, outstanding6false0us-gaap_LineOfCreditFacilityRemainingBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse47850000004785000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAmount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 falsefalsePortion of unused credit to provide liquidity support7true0so_FinancingTextualsAbstractsofalsenadurationFinancing Textuals Abstract.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringFinancing Textuals Abstract.falsefalseFinancing (Textuals) [Abstract]8false0so_LongTermDebtAndCapitalLeaseObligationMaturitiesRePaymentsInNextTwelveMonthssofalsecreditinstantLong Term Debt and Capital Lease Obligation Maturities Re payments In Next Twelve Months.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse13000000001300000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLong Term Debt and Capital Lease Obligation Maturities Re payments In Next Twelve Months.No authoritative reference available.falsefalseLong term debt maturities in 20119false0so_LongTermDebtAndCapitalLeaseObligationMaturitiesRePaymentsInYearTwosofalsecreditinstantLong Term Debt and Capital Lease Obligation Maturities Re payments In Year Two.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse18000000001800000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLong Term Debt and Capital Lease Obligation Maturities Re payments In Year Two.No authoritative reference available.falsefalseLong term debt maturities in 201210false0so_LongTermDebtAndCapitalLeaseObligationMaturitiesRePaymentsInYearThreesofalsecreditinstantLong Term Debt and Capital Lease Obligation Maturities Re payments In Year Three.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse17000000001700000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLong Term Debt and Capital Lease Obligation Maturities Re payments In Year Three.No authoritative reference available.falsefalseLong term debt maturities in 201311false0so_LongTermDebtAndCapitalLeaseObligationMaturitiesRePaymentsInYearFoursofalsecreditinstantLong Term Debt and Capital Lease Obligation Maturities Re payments In Year Four.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse441000000441000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLong Term Debt and Capital Lease Obligation Maturities Re payments In Year Four.No authoritative reference available.falsefalseLong term debt maturities in 201412false0so_LongTermDebtAndCapitalLeaseObligationMaturitiesRePaymentsInYearFivesofalsecreditinstantLong Term Debt and Capital Lease Obligation Maturities Re payments In Year Five.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse12000000001200000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLong Term Debt and Capital Lease Obligation Maturities Re payments In Year Five.No authoritative reference available.falsefalseLong term debt maturities in 201513false0so_AverageCommitmentFeessofalsenadurationAverage Commitment fees.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse001/2 of 1% or lessfalsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringAverage Commitment fees.No authoritative reference available.falsefalseAverage commitment fees14false0so_RatioOfIndebtednessToCapitalizationCovenantsofalsenadurationRatio of indebtedness to capitalization covenant.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.650.65falsefalsefalsefalsefalse2falsetruefalse00falsefalsefalsefalsefalseOtherus-types:percentItemTypepureRatio of indebtedness to capitalization covenant.No authoritative reference available.falsefalseRatio of indebtedness to capitalization covenant15false0so_AmountOfVariableRatePollutionControlRevenueBondsOutstandingRequiringLiquiditySupportsofalsedebitinstantAmount of Variable rate Pollution Control revenue Bonds Outstanding requiring Liquidity support.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse13000000001300000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAmount of Variable rate Pollution Control revenue Bonds Outstanding requiring Liquidity support.No authoritative reference available.falsefalseAmount of variable rate pollution control revenue bonds outstanding requiring liquidity support16false0us-gaap_CommercialPaperus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse13000000001300000000falsefalsefalsefalsefalse2truefalsefalse638000000638000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryCarrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Subparagraph a(3) -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 13 -Subparagraph 2 -Article 9 falsefalseAmount of commercial paper outstanding17false0us-gaap_ShorttermDebtMaximumAmountOutstandingDuringPeriodus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse13000000001300000000falsefalsefalsefalsefalse2truefalsefalse14000000001400000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryFor the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, the maximum amount borrowed at any time during the period.No authoritative reference available.falsefalseMaximum amount outstanding for commercial paperpaper18false0us-gaap_ShorttermDebtAverageOutstandingAmountus-gaaptruecreditdurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse690000000690000000falsefalsefalsefalsefalse2truefalsefalse956000000956000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryFor the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, average borrowings during the period.No authoritative reference available.falsefalseAverage amount outstanding for short-term debt19false0us-gaap_ShortTermDebtWeightedAverageInterestRateus-gaaptruenainstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.0030.003falsefalsefalsefalsefalse2truetruefalse0.0030.003falsefalsefalsefalsefalseOtherus-types:percentItemTypepureReflects the calculation as of the balance-sheet date of the average interest rate weighted by the amount of short-term debt outstanding by type or by instrument at that time.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Subparagraph b -Article 5 falsefalseAverage annual interest rate on short-term debt20false0so_ShortTermDebtWeightedAverageInterestRatessofalsenadurationShort Term Debt Weighted Average Interest Rates.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.0030.003falsefalsefalsefalsefalse2truetruefalse0.0040.004falsefalsefalsefalsefalseOtherus-types:percentItemTypepureShort Term Debt Weighted Average Interest Rates.No authoritative reference available.falsefalseAverage annual interest rate on short-term debt21false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://southerncompany.com/role/financingdetailstextual1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse3falsefalseUSDtruefalse{dei_LegalEntityAxis} : Southern Company [Member] 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Parent_Company_Memberhttp://www.sec.gov/CIK0000092122instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseSouthern Company [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ParentCompanyMemberdei_LegalEntityAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$4falsefalseUSDtruefalse{dei_LegalEntityAxis} : Southern Company [Member] 12/31/2009 USD ($) $BalanceAsOf_31Dec2009_Parent_Company_Memberhttp://www.sec.gov/CIK0000092122instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseSouthern Company [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ParentCompanyMemberdei_LegalEntityAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseSouthern Company [Member]22true0us-gaap_InvestmentHoldingsLineItemsus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringLine items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.falsefalseInvestment Holdings [Line Items]23false0us-gaap_SeniorNotesus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse16000000001600000000falsefalsefalsefalsefalse2truefalsefalse18000000001800000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryIncluding the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 9 falsefalseSenior notes outstanding24false0us-gaap_LineOfCreditFacilityRemainingBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse950000000950000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAmount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 falsefalsePortion of unused credit to provide liquidity support26false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://southerncompany.com/role/financingdetailstextual1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse5falsefalseUSDtruefalse{dei_LegalEntityAxis} : Southern Company [Member] {us-gaap_InvestmentTypeAxis} : Senior Notes [Member] 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Parent_Company_Member_Senior_Notes_Memberhttp://www.sec.gov/CIK0000092122instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseSouthern Company [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ParentCompanyMemberdei_LegalEntityAxisexplicitMemberfalsefalseSenior Notes [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_SeniorNotesMemberus-gaap_InvestmentTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseSouthern Company [Member] | Senior Notes [Member]27true0us-gaap_InvestmentHoldingsLineItemsus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringLine items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.falsefalseInvestment Holdings [Line Items]28false0us-gaap_DebtInstrumentFaceAmountus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse400000000400000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 21 -Paragraph 16, 20 falsefalseIssuance of senior notes30false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://southerncompany.com/role/financingdetailstextual1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse6falsefalseUSDtruefalse{dei_LegalEntityAxis} : Operating Companies [Member] {us-gaap_InvestmentTypeAxis} : Senior Notes [Member] 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Senior_Notes_Member_Operating_Companies_Memberhttp://www.sec.gov/CIK0000092122instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseOperating Companies [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldiso_OperatingCompaniesMemberdei_LegalEntityAxisexplicitMemberfalsefalseSenior Notes [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_SeniorNotesMemberus-gaap_InvestmentTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseOperating Companies [Member] | Senior Notes [Member]31true0us-gaap_InvestmentHoldingsLineItemsus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringLine items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.falsefalseInvestment Holdings [Line Items]32false0us-gaap_DebtInstrumentFaceAmountus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse25000000002500000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 21 -Paragraph 16, 20 falsefalseIssuance of senior notes34false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://southerncompany.com/role/financingdetailstextual1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse7falsefalseUSDtruefalse{dei_LegalEntityAxis} : Georgia Power [Member] 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Georgia_Power_Memberhttp://www.sec.gov/CIK0000092122instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseGeorgia Power [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldiso_GeorgiaPowerMemberdei_LegalEntityAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseGeorgia Power [Member]35true0us-gaap_InvestmentHoldingsLineItemsus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringLine items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.falsefalseInvestment Holdings [Line Items]36false0so_RemarketingOfPuttableVariableRatePollutionControlBondssofalsecreditinstantRemarketing of puttable variable rate pollution control bonds.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse137000000137000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryRemarketing of puttable variable rate pollution control bonds.No authoritative reference available.falsefalseRemarketing of puttable variable rate pollution control bonds37false0us-gaap_LineOfCreditFacilityRemainingBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse17030000001703000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAmount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 falsefalsePortion of unused credit to provide liquidity support38false0so_LiquiditySupportIncreasedByRemarketingsOfPollutionControlRevenueBondssofalsedebitinstantLiquidity support increased by Remarketings of pollution control revenue bonds.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse522000000522000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLiquidity support increased by Remarketings of pollution control revenue bonds.No authoritative reference available.falsefalseLiquidity support increased by Remarketings of pollution control revenue bonds40false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://southerncompany.com/role/financingdetailstextual1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse8falsefalseUSDtruefalse{dei_LegalEntityAxis} : Georgia Power [Member] {us-gaap_InvestmentTypeAxis} : Senior Notes [Member] 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Senior_Notes_Member_Georgia_Power_Memberhttp://www.sec.gov/CIK0000092122instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseGeorgia Power [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldiso_GeorgiaPowerMemberdei_LegalEntityAxisexplicitMemberfalsefalseSenior Notes [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_SeniorNotesMemberus-gaap_InvestmentTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseGeorgia Power [Member] | Senior Notes [Member]41true0us-gaap_InvestmentHoldingsLineItemsus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringLine items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.falsefalseInvestment Holdings [Line Items]42false0us-gaap_DebtInstrumentFaceAmountus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse300000000300000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 21 -Paragraph 16, 20 falsefalseIssuance of senior notes44false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://southerncompany.com/role/financingdetailstextual1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse9falsefalseUSDtruefalse{dei_LegalEntityAxis} : Gulf Power [Member] 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Gulf_Power_Memberhttp://www.sec.gov/CIK0000092122instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseGulf Power [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldiso_GulfPowerMemberdei_LegalEntityAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseGulf Power [Member]45true0us-gaap_InvestmentHoldingsLineItemsus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringLine items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.falsefalseInvestment Holdings [Line Items]46false0us-gaap_LineOfCreditFacilityRemainingBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse240000000240000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAmount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 falsefalsePortion of unused credit to provide liquidity support48false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://southerncompany.com/role/financingdetailstextual1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse10falsefalseUSDtruefalse{dei_LegalEntityAxis} : Mississippi Power [Member] 1/1/2010 - 12/31/2010 USD ($) $TwelveMonthsEnded_31Dec2010_Mississippi_Power_Memberhttp://www.sec.gov/CIK0000092122duration2010-01-01T00:00:002010-12-31T00:00:00falsefalseMississippi Power [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldiso_MississippiPowerMemberdei_LegalEntityAxisexplicitMemberPureStandardhttp://www.xbrl.org/2003/instancepurexbrli0USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseMississippi Power [Member]49true0us-gaap_InvestmentHoldingsLineItemsus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringLine items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.falsefalseInvestment Holdings [Line Items]50false0so_BankOneYearTermLoanAgreementPrincipalAmountsofalsecreditdurationBank one year term loan agreement principal amount.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse125000000125000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryBank one year term loan agreement principal amount.No authoritative reference available.falsefalseBank one-year term loan agreement principal amount.51false0so_RevenueBondssofalsecreditinstantRevenue Bonds.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse100000000100000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryRevenue Bonds.No authoritative reference available.falsefalseRevenue Bonds52false0us-gaap_LongTermDebtPercentageBearingFixedInterestRateus-gaaptruenainstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truetruefalse0.02250.0225falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherus-types:percentItemTypepureThe portion of the carrying amount of long-term borrowings outstanding as of the balance-sheet date, including current maturities, which accrues interest at a set, unchanging rateNo authoritative reference available.falsefalseFixed Interest Rate on Revenue Bonds53false0us-gaap_LineOfCreditFacilityRemainingBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse161000000161000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryAmount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 falsefalsePortion of unused credit to provide liquidity support55false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://southerncompany.com/role/financingdetailstextual1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse11falsefalseUSDtruefalse{dei_LegalEntityAxis} : Mississippi Power [Member] {us-gaap_InvestmentTypeAxis} : 2.25 fixed interest rate [Member] 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Mississippi_Power_Member_Two_Point_Two_Five_Fixed_Interest_Rate_Memberhttp://www.sec.gov/CIK0000092122instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseMississippi Power [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldiso_MississippiPowerMemberdei_LegalEntityAxisexplicitMemberfalsefalse2.25 fixed interest rate [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldiso_TwoPointTwoFiveFixedInterestRateMemberus-gaap_InvestmentTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseMississippi Power [Member] | 2.25 fixed interest rate [Member]56true0us-gaap_InvestmentHoldingsLineItemsus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringLine items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.falsefalseInvestment Holdings [Line Items]57false0so_RevenueBondssofalsecreditinstantRevenue Bonds.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse5000000050000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryRevenue Bonds.No authoritative reference available.falsefalseRevenue Bonds59false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://southerncompany.com/role/financingdetailstextual1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse12falsefalseUSDtruefalse{dei_LegalEntityAxis} : Mississippi Power [Member] {us-gaap_InvestmentTypeAxis} : Floating interest rate [Member] 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Mississippi_Power_Member_Floating_Interest_Rate_Memberhttp://www.sec.gov/CIK0000092122instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseMississippi Power [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldiso_MississippiPowerMemberdei_LegalEntityAxisexplicitMemberfalsefalseFloating interest rate [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldiso_FloatingInterestRateMemberus-gaap_InvestmentTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseMississippi Power [Member] | Floating interest rate [Member]60true0us-gaap_InvestmentHoldingsLineItemsus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringLine items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.falsefalseInvestment Holdings [Line Items]61false0so_RevenueBondssofalsecreditinstantRevenue Bonds.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse5000000050000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryRevenue Bonds.No authoritative reference available.falsefalseRevenue Bonds63false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://southerncompany.com/role/financingdetailstextual1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse13falsefalseUSDtruefalse{dei_LegalEntityAxis} : Traditional Operating Companies [Member] 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Traditional_Operating_Companies_Memberhttp://www.sec.gov/CIK0000092122instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseTraditional Operating Companies [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldiso_TraditionalOperatingCompaniesMemberdei_LegalEntityAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$14falsefalseUSDtruefalse{dei_LegalEntityAxis} : Traditional Operating Companies [Member] 12/31/2009 USD ($) $BalanceAsOf_31Dec2009_Traditional_Operating_Companies_Memberhttp://www.sec.gov/CIK0000092122instant2009-12-31T00:00:000001-01-01T00:00:00falsefalseTraditional Operating Companies [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldiso_TraditionalOperatingCompaniesMemberdei_LegalEntityAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseTraditional Operating Companies [Member]64true0us-gaap_InvestmentHoldingsLineItemsus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringLine items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.falsefalseInvestment Holdings [Line Items]65false0us-gaap_LoansPayableToBankCurrentus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse615000000615000000falsefalsefalsefalsefalse2truefalsefalse490000000490000000falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryCarrying value as of the balance sheet date of current portion of long-term loans payable to bank due within one year or the operating cycle if longer.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 20 -Article 5 falsefalseBank term loans outstanding67false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://southerncompany.com/role/financingdetailstextual1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse15falsefalseUSDtruefalse{us-gaap_InvestmentTypeAxis} : Senior Notes [Member] 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Senior_Notes_Memberhttp://www.sec.gov/CIK0000092122instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseSenior Notes [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_SeniorNotesMemberus-gaap_InvestmentTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseSenior Notes [Member]68true0us-gaap_InvestmentHoldingsLineItemsus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringLine items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.falsefalseInvestment Holdings [Line Items]69false0us-gaap_DebtInstrumentFaceAmountus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse29000000002900000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 21 -Paragraph 16, 20 falsefalseIssuance of senior notes71false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://southerncompany.com/role/financingdetailstextual1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse16falsefalseUSDtruefalse{us-gaap_InvestmentTypeAxis} : Secured Debt [Member] 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Secured_Debt_Memberhttp://www.sec.gov/CIK0000092122instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseSecured Debt [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_SecuredDebtMemberus-gaap_InvestmentTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseSecured Debt [Member]72true0us-gaap_InvestmentHoldingsLineItemsus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringLine items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.falsefalseInvestment Holdings [Line Items]73false0us-gaap_LongtermPollutionControlBondCurrentAndNoncurrentus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse194000000194000000falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryRepresents the current and noncurrent portions of a debt security issued by a state, certain agencies or authorities, a local government, or development corporation to finance the construction of air- or water-pollution control facilities or sewage or solid waste disposal facilities pursuant to federal law. The bonds are backed by the credit of the beneficiary of the financing rather than the credit of the issuer. New issues of these bonds are prohibited under the 1986 Tax Law.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20, 22 -Article 5 falsefalsePollution control revenue bonds, outstanding75false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://southerncompany.com/role/financingdetailstextual1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalse17falsefalseUSDtruefalse{us-gaap_InvestmentTypeAxis} : Trust Preferred Securities Subject To Mandatory Redemption [Member] 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Trust_Preferred_Securities_Subject_To_Mandatory_Redemption_Memberhttp://www.sec.gov/CIK0000092122instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseTrust Preferred Securities Subject To Mandatory Redemption [Member]us-gaap_InvestmentTypeAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_TrustPreferredSecuritiesSubjectToMandatoryRedemptionMemberus-gaap_InvestmentTypeAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseTrust Preferred Securities Subject To Mandatory Redemption [Member]76true0us-gaap_InvestmentHoldingsLineItemsus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringLine items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.falsefalseInvestment Holdings [Line Items]77false0us-gaap_SharesSubjectToMandatoryRedemptionSettlementTermsMaximumAmountus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse400000000400000000falsetruefalsefalsefalse2falsefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryThe maximum amount that the issuer could be required to pay to redeem the instrument by physical settlement, if applicable.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 150 -Paragraph 27 -Subparagraph c falsefalsePreferred securities, outstanding264Financing (Details Textual) (USD $)NoRoundingUnKnownUnKnownUnKnowntruetrue