2.2.0.25truefalse06061 - Disclosure - Financing (Details 1)truefalseIn Millionsfalse1falsefalseUSDfalsefalse12/31/2010 USD ($) $BalanceAsOf_31Dec2010http://www.sec.gov/CIK0000092122instant2010-12-31T00:00:000001-01-01T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170SharesStandardhttp://www.xbrl.org/2003/instancesharesxbrli0PureStandardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$2true0us-gaap_LineOfCreditFacilityAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseCredit arrangements by company3false0us-gaap_LineOfCreditFacilityMaximumBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse47970000004797falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryMaximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 129 -Paragraph 2, 4 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 falsefalseTotal4false0us-gaap_LineOfCreditFacilityRemainingBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse47850000004785falsefalsefalsefalsefalseMonetaryxbrli: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 falsefalseUnused5false0so_ExecutableTermLoansForOneYearsofalsecreditinstantExecutable Term Loans For One Year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse927000000927falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryExecutable Term Loans For One Year.No authoritative reference available.falsefalseExecutable Term- Loans, One Year6false0so_ExecutableTermLoansForTwoYearssofalsecreditinstantExecutable Term Loans For Two Years.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse8100000081falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryExecutable Term Loans For Two Years.No authoritative reference available.falsefalseExecutable Term- Loans, Two Years7false0so_LineOfCreditExpiryCurrentYearsofalsecreditinstantLine of credit expiry current year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse15620000001562falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine of credit expiry current year.No authoritative reference available.falsefalseExpires, 20118false0so_LineOfCreditExpiryYearOnesofalsecreditinstantLine Of Credit Expiry Year 1.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse32350000003235falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine Of Credit Expiry Year 1.No authoritative reference available.falsefalseExpires, 20129false0so_LineOfCreditExpiryYearTwosofalsecreditinstantLine Of Credit Expiry Year 2.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine Of Credit Expiry Year 2.No authoritative reference available.falsefalseExpires, 201310false0so_BankCreditArrangementsTermLoanOptionExpiresWithInOneYearsofalsecreditinstantBank credit arrangements term out expires with in one year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse10080000001008falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryBank credit arrangements term out expires with in one year.No authoritative reference available.falsefalseExpires Within One Year, Term Loan Option11false0so_BankCreditArrangementsNoTermLoanOptionExpiresWithInOneYearsofalsecreditinstantBank credit arrangements no term out expires with in one year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse554000000554falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryBank credit arrangements no term out expires with in one year.No authoritative reference available.falsefalseExpires Within One Year, No Term Loan Option12false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://southerncompany.com/role/financingdetails11falsefalsefalse00falsefalsefalsefalsefalse2falsefalseUSDtruefalse{dei_LegalEntityAxis} : Southern Company [Member] 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Parent_Company_Memberhttp://www.sec.gov/CIK0000092122instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseSouthern Company [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldius-gaap_ParentCompanyMemberdei_LegalEntityAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseSouthern Company [Member]13true0us-gaap_LineOfCreditFacilityAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseCredit arrangements by company14false0us-gaap_LineOfCreditFacilityMaximumBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse950000000950falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryMaximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 129 -Paragraph 2, 4 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 falsefalseTotal15false0us-gaap_LineOfCreditFacilityRemainingBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse950000000950falsefalsefalsefalsefalseMonetaryxbrli: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 falsefalseUnused16false0so_ExecutableTermLoansForOneYearsofalsecreditinstantExecutable Term Loans For One Year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryExecutable Term Loans For One Year.No authoritative reference available.falsefalseExecutable Term- Loans, One Year17false0so_ExecutableTermLoansForTwoYearssofalsecreditinstantExecutable Term Loans For Two Years.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryExecutable Term Loans For Two Years.No authoritative reference available.falsefalseExecutable Term- Loans, Two Years18false0so_LineOfCreditExpiryCurrentYearsofalsecreditinstantLine of credit expiry current year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine of credit expiry current year.No authoritative reference available.falsefalseExpires, 201119false0so_LineOfCreditExpiryYearOnesofalsecreditinstantLine Of Credit Expiry Year 1.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse950000000950falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine Of Credit Expiry Year 1.No authoritative reference available.falsefalseExpires, 201220false0so_LineOfCreditExpiryYearTwosofalsecreditinstantLine Of Credit Expiry Year 2.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine Of Credit Expiry Year 2.No authoritative reference available.falsefalseExpires, 201321false0so_BankCreditArrangementsTermLoanOptionExpiresWithInOneYearsofalsecreditinstantBank credit arrangements term out expires with in one year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryBank credit arrangements term out expires with in one year.No authoritative reference available.falsefalseExpires Within One Year, Term Loan Option22false0so_BankCreditArrangementsNoTermLoanOptionExpiresWithInOneYearsofalsecreditinstantBank credit arrangements no term out expires with in one year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryBank credit arrangements no term out expires with in one year.No authoritative reference available.falsefalseExpires Within One Year, No Term Loan Option23false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://southerncompany.com/role/financingdetails11falsefalsefalse00falsefalsefalsefalsefalse3falsefalseUSDtruefalse{dei_LegalEntityAxis} : Alabama Power [Member] 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Alabama_Power_Memberhttp://www.sec.gov/CIK0000092122instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseAlabama Power [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldiso_AlabamaPowerMemberdei_LegalEntityAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseAlabama Power [Member]24true0us-gaap_LineOfCreditFacilityAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseCredit arrangements by company25false0us-gaap_LineOfCreditFacilityMaximumBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse12710000001271falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryMaximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 129 -Paragraph 2, 4 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 falsefalseTotal26false0us-gaap_LineOfCreditFacilityRemainingBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse12710000001271falsefalsefalsefalsefalseMonetaryxbrli: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 falsefalseUnused27false0so_ExecutableTermLoansForOneYearsofalsecreditinstantExecutable Term Loans For One Year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse372000000372falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryExecutable Term Loans For One Year.No authoritative reference available.falsefalseExecutable Term- Loans, One Year28false0so_ExecutableTermLoansForTwoYearssofalsecreditinstantExecutable Term Loans For Two Years.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryExecutable Term Loans For Two Years.No authoritative reference available.falsefalseExecutable Term- Loans, Two Years29false0so_LineOfCreditExpiryCurrentYearsofalsecreditinstantLine of credit expiry current year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse506000000506falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine of credit expiry current year.No authoritative reference available.falsefalseExpires, 201130false0so_LineOfCreditExpiryYearOnesofalsecreditinstantLine Of Credit Expiry Year 1.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse765000000765falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine Of Credit Expiry Year 1.No authoritative reference available.falsefalseExpires, 201231false0so_LineOfCreditExpiryYearTwosofalsecreditinstantLine Of Credit Expiry Year 2.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine Of Credit Expiry Year 2.No authoritative reference available.falsefalseExpires, 201332false0so_BankCreditArrangementsTermLoanOptionExpiresWithInOneYearsofalsecreditinstantBank credit arrangements term out expires with in one year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse372000000372falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryBank credit arrangements term out expires with in one year.No authoritative reference available.falsefalseExpires Within One Year, Term Loan Option33false0so_BankCreditArrangementsNoTermLoanOptionExpiresWithInOneYearsofalsecreditinstantBank credit arrangements no term out expires with in one year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse134000000134falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryBank credit arrangements no term out expires with in one year.No authoritative reference available.falsefalseExpires Within One Year, No Term Loan Option34false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://southerncompany.com/role/financingdetails11falsefalsefalse00falsefalsefalsefalsefalse4falsefalseUSDtruefalse{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_LineOfCreditFacilityAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseCredit arrangements by company36false0us-gaap_LineOfCreditFacilityMaximumBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse17150000001715falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryMaximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 129 -Paragraph 2, 4 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 falsefalseTotal37false0us-gaap_LineOfCreditFacilityRemainingBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse17030000001703falsefalsefalsefalsefalseMonetaryxbrli: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 falsefalseUnused38false0so_ExecutableTermLoansForOneYearsofalsecreditinstantExecutable Term Loans For One Year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse220000000220falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryExecutable Term Loans For One Year.No authoritative reference available.falsefalseExecutable Term- Loans, One Year39false0so_ExecutableTermLoansForTwoYearssofalsecreditinstantExecutable Term Loans For Two Years.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse4000000040falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryExecutable Term Loans For Two Years.No authoritative reference available.falsefalseExecutable Term- Loans, Two Years40false0so_LineOfCreditExpiryCurrentYearsofalsecreditinstantLine of credit expiry current year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse595000000595falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine of credit expiry current year.No authoritative reference available.falsefalseExpires, 201141false0so_LineOfCreditExpiryYearOnesofalsecreditinstantLine Of Credit Expiry Year 1.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse11200000001120falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine Of Credit Expiry Year 1.No authoritative reference available.falsefalseExpires, 201242false0so_LineOfCreditExpiryYearTwosofalsecreditinstantLine Of Credit Expiry Year 2.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine Of Credit Expiry Year 2.No authoritative reference available.falsefalseExpires, 201343false0so_BankCreditArrangementsTermLoanOptionExpiresWithInOneYearsofalsecreditinstantBank credit arrangements term out expires with in one year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse260000000260falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryBank credit arrangements term out expires with in one year.No authoritative reference available.falsefalseExpires Within One Year, Term Loan Option44false0so_BankCreditArrangementsNoTermLoanOptionExpiresWithInOneYearsofalsecreditinstantBank credit arrangements no term out expires with in one year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse335000000335falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryBank credit arrangements no term out expires with in one year.No authoritative reference available.falsefalseExpires Within One Year, No Term Loan Option45false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://southerncompany.com/role/financingdetails11falsefalsefalse00falsefalsefalsefalsefalse5falsefalseUSDtruefalse{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]46true0us-gaap_LineOfCreditFacilityAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseCredit arrangements by company47false0us-gaap_LineOfCreditFacilityMaximumBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse240000000240falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryMaximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 129 -Paragraph 2, 4 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 falsefalseTotal48false0us-gaap_LineOfCreditFacilityRemainingBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse240000000240falsefalsefalsefalsefalseMonetaryxbrli: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 falsefalseUnused49false0so_ExecutableTermLoansForOneYearsofalsecreditinstantExecutable Term Loans For One Year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse210000000210falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryExecutable Term Loans For One Year.No authoritative reference available.falsefalseExecutable Term- Loans, One Year50false0so_ExecutableTermLoansForTwoYearssofalsecreditinstantExecutable Term Loans For Two Years.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryExecutable Term Loans For Two Years.No authoritative reference available.falsefalseExecutable Term- Loans, Two Years51false0so_LineOfCreditExpiryCurrentYearsofalsecreditinstantLine of credit expiry current year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse240000000240falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine of credit expiry current year.No authoritative reference available.falsefalseExpires, 201152false0so_LineOfCreditExpiryYearOnesofalsecreditinstantLine Of Credit Expiry Year 1.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine Of Credit Expiry Year 1.No authoritative reference available.falsefalseExpires, 201253false0so_LineOfCreditExpiryYearTwosofalsecreditinstantLine Of Credit Expiry Year 2.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine Of Credit Expiry Year 2.No authoritative reference available.falsefalseExpires, 201354false0so_BankCreditArrangementsTermLoanOptionExpiresWithInOneYearsofalsecreditinstantBank credit arrangements term out expires with in one year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse210000000210falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryBank credit arrangements term out expires with in one year.No authoritative reference available.falsefalseExpires Within One Year, Term Loan Option55false0so_BankCreditArrangementsNoTermLoanOptionExpiresWithInOneYearsofalsecreditinstantBank credit arrangements no term out expires with in one year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse3000000030falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryBank credit arrangements no term out expires with in one year.No authoritative reference available.falsefalseExpires Within One Year, No Term Loan Option56false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://southerncompany.com/role/financingdetails11falsefalsefalse00falsefalsefalsefalsefalse6falsefalseUSDtruefalse{dei_LegalEntityAxis} : Mississippi Power [Member] 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Mississippi_Power_Memberhttp://www.sec.gov/CIK0000092122instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseMississippi Power [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldiso_MississippiPowerMemberdei_LegalEntityAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170PureStandardhttp://www.xbrl.org/2003/instancepurexbrli0USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseMississippi Power [Member]57true0us-gaap_LineOfCreditFacilityAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseCredit arrangements by company58false0us-gaap_LineOfCreditFacilityMaximumBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse161000000161falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryMaximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 129 -Paragraph 2, 4 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 falsefalseTotal59false0us-gaap_LineOfCreditFacilityRemainingBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse161000000161falsefalsefalsefalsefalseMonetaryxbrli: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 falsefalseUnused60false0so_ExecutableTermLoansForOneYearsofalsecreditinstantExecutable Term Loans For One Year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse6500000065falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryExecutable Term Loans For One Year.No authoritative reference available.falsefalseExecutable Term- Loans, One Year61false0so_ExecutableTermLoansForTwoYearssofalsecreditinstantExecutable Term Loans For Two Years.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse4100000041falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryExecutable Term Loans For Two Years.No authoritative reference available.falsefalseExecutable Term- Loans, Two Years62false0so_LineOfCreditExpiryCurrentYearsofalsecreditinstantLine of credit expiry current year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse161000000161falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine of credit expiry current year.No authoritative reference available.falsefalseExpires, 201163false0so_LineOfCreditExpiryYearOnesofalsecreditinstantLine Of Credit Expiry Year 1.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine Of Credit Expiry Year 1.No authoritative reference available.falsefalseExpires, 201264false0so_LineOfCreditExpiryYearTwosofalsecreditinstantLine Of Credit Expiry Year 2.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine Of Credit Expiry Year 2.No authoritative reference available.falsefalseExpires, 201365false0so_BankCreditArrangementsTermLoanOptionExpiresWithInOneYearsofalsecreditinstantBank credit arrangements term out expires with in one year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse106000000106falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryBank credit arrangements term out expires with in one year.No authoritative reference available.falsefalseExpires Within One Year, Term Loan Option66false0so_BankCreditArrangementsNoTermLoanOptionExpiresWithInOneYearsofalsecreditinstantBank credit arrangements no term out expires with in one year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse5500000055falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryBank credit arrangements no term out expires with in one year.No authoritative reference available.falsefalseExpires Within One Year, No Term Loan Option67false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://southerncompany.com/role/financingdetails11falsefalsefalse00falsefalsefalsefalsefalse7falsefalseUSDtruefalse{dei_LegalEntityAxis} : Southern Power [Member] 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Southern_Power_Memberhttp://www.sec.gov/CIK0000092122instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseSouthern Power [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldiso_SouthernPowerMemberdei_LegalEntityAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseSouthern Power [Member]68true0us-gaap_LineOfCreditFacilityAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseCredit arrangements by company69false0us-gaap_LineOfCreditFacilityMaximumBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse400000000400falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryMaximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 129 -Paragraph 2, 4 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 falsefalseTotal70false0us-gaap_LineOfCreditFacilityRemainingBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse400000000400falsefalsefalsefalsefalseMonetaryxbrli: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 falsefalseUnused71false0so_ExecutableTermLoansForOneYearsofalsecreditinstantExecutable Term Loans For One Year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryExecutable Term Loans For One Year.No authoritative reference available.falsefalseExecutable Term- Loans, One Year72false0so_ExecutableTermLoansForTwoYearssofalsecreditinstantExecutable Term Loans For Two Years.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryExecutable Term Loans For Two Years.No authoritative reference available.falsefalseExecutable Term- Loans, Two Years73false0so_LineOfCreditExpiryCurrentYearsofalsecreditinstantLine of credit expiry current year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine of credit expiry current year.No authoritative reference available.falsefalseExpires, 201174false0so_LineOfCreditExpiryYearOnesofalsecreditinstantLine Of Credit Expiry Year 1.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse400000000400falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine Of Credit Expiry Year 1.No authoritative reference available.falsefalseExpires, 201275false0so_LineOfCreditExpiryYearTwosofalsecreditinstantLine Of Credit Expiry Year 2.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine Of Credit Expiry Year 2.No authoritative reference available.falsefalseExpires, 201376false0so_BankCreditArrangementsTermLoanOptionExpiresWithInOneYearsofalsecreditinstantBank credit arrangements term out expires with in one year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryBank credit arrangements term out expires with in one year.No authoritative reference available.falsefalseExpires Within One Year, Term Loan Option77false0so_BankCreditArrangementsNoTermLoanOptionExpiresWithInOneYearsofalsecreditinstantBank credit arrangements no term out expires with in one year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryBank credit arrangements no term out expires with in one year.No authoritative reference available.falsefalseExpires Within One Year, No Term Loan Option78false0natruenanaNo definition available.falsetruefalsefalsefalsefalsefalsefalsefalsefalsehttp://southerncompany.com/role/financingdetails11falsefalsefalse00falsefalsefalsefalsefalse8falsefalseUSDtruefalse{dei_LegalEntityAxis} : Other Subsidiaries [Member] 12/31/2010 USD ($) $BalanceAsOf_31Dec2010_Other_Subsidiaries_Memberhttp://www.sec.gov/CIK0000092122instant2010-12-31T00:00:000001-01-01T00:00:00falsefalseOther Subsidiaries [Member]dei_LegalEntityAxisxbrldihttp://xbrl.org/2006/xbrldiso_OtherSubsidiariesMemberdei_LegalEntityAxisexplicitMemberUSDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$OthernaNo definition available.No authoritative reference available.falsefalseOther Subsidiaries [Member]79true0us-gaap_LineOfCreditFacilityAbstractus-gaaptruenadurationNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1falsefalsefalse00falsefalsefalsefalsefalseOtherxbrli:stringItemTypestringNo definition available.falsefalseCredit arrangements by company80false0us-gaap_LineOfCreditFacilityMaximumBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse6000000060falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryMaximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 129 -Paragraph 2, 4 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 falsefalseTotal81false0us-gaap_LineOfCreditFacilityRemainingBorrowingCapacityus-gaaptruecreditinstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse6000000060falsefalsefalsefalsefalseMonetaryxbrli: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 falsefalseUnused82false0so_ExecutableTermLoansForOneYearsofalsecreditinstantExecutable Term Loans For One Year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse6000000060falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryExecutable Term Loans For One Year.No authoritative reference available.falsefalseExecutable Term- Loans, One Year83false0so_ExecutableTermLoansForTwoYearssofalsecreditinstantExecutable Term Loans For Two Years.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryExecutable Term Loans For Two Years.No authoritative reference available.falsefalseExecutable Term- Loans, Two Years84false0so_LineOfCreditExpiryCurrentYearsofalsecreditinstantLine of credit expiry current year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse6000000060falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine of credit expiry current year.No authoritative reference available.falsefalseExpires, 201185false0so_LineOfCreditExpiryYearOnesofalsecreditinstantLine Of Credit Expiry Year 1.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine Of Credit Expiry Year 1.No authoritative reference available.falsefalseExpires, 201286false0so_LineOfCreditExpiryYearTwosofalsecreditinstantLine Of Credit Expiry Year 2.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryLine Of Credit Expiry Year 2.No authoritative reference available.falsefalseExpires, 201387false0so_BankCreditArrangementsTermLoanOptionExpiresWithInOneYearsofalsecreditinstantBank credit arrangements term out expires with in one year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse6000000060falsefalsefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryBank credit arrangements term out expires with in one year.No authoritative reference available.falsefalseExpires Within One Year, Term Loan Option88false0so_BankCreditArrangementsNoTermLoanOptionExpiresWithInOneYearsofalsecreditinstantBank credit arrangements no term out expires with in one year.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseverboselabel1truefalsefalse00falsetruefalsefalsefalseMonetaryxbrli:monetaryItemTypemonetaryBank credit arrangements no term out expires with in one year.No authoritative reference available.falsefalseExpires Within One Year, No Term Loan Option187Financing (Details 1) (USD $)MillionsUnKnownUnKnownUnKnownfalsetrue