2.4.0.82405410 - Disclosure - Investments and Derivative Instruments (Valuation Allowance Mortgage Loans) (Details)truefalseIn Millions, unless otherwise specifiedfalse1false USDfalsefalse$D2012Q4YTD_hig_ScheduleOfAvailableForSaleSecuritiesTypesOfMortgageLoansAxis_hig_CommercialMemberhttp://www.sec.gov/CIK0000045947duration2012-01-01T00:00:002012-12-31T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$D2011Q4YTD_hig_ScheduleOfAvailableForSaleSecuritiesTypesOfMortgageLoansAxis_hig_CommercialMemberhttp://www.sec.gov/CIK0000045947duration2011-01-01T00:00:002011-12-31T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$3false USDfalsefalse$D2010Q4YTD_hig_ScheduleOfAvailableForSaleSecuritiesTypesOfMortgageLoansAxis_hig_CommercialMemberhttp://www.sec.gov/CIK0000045947duration2010-01-01T00:00:002010-12-31T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 4us-gaap_MovementInValuationAllowancesAndReservesRollForwardus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Movement in Valuation allowance and reserves2false 5us-gaap_AllowanceForLoanAndLeaseLossesRealEstateus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsetruetruenegatedPeriodEndLabel1truefalsefalse-14000000-14USD$falsetruefalse2truefalsefalse-23000000-23USD$falsetruefalse3falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 60 -Paragraph 47 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 310 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6873192&loc=d3e21338-158488 false2Balance, end of period3false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse3false USDtruefalse$D2012Q4YTD_hig_ScheduleOfAvailableForSaleSecuritiesTypesOfMortgageLoansAxis_hig_CommercialMemberhttp://www.sec.gov/CIK0000045947duration2012-01-01T00:00:002012-12-31T00:00:00falsefalseCommercial [Member]hig_ScheduleOfAvailableForSaleSecuritiesTypesOfMortgageLoansAxisxbrldihttp://xbrl.org/2006/xbrldihig_CommercialMemberhig_ScheduleOfAvailableForSaleSecuritiesTypesOfMortgageLoansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Commercial [Member]4true 4us-gaap_MovementInValuationAllowancesAndReservesRollForwardus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Movement in Valuation allowance and reserves5false 5us-gaap_AllowanceForLoanAndLeaseLossesRealEstateus-gaap_truecreditinstantfalsefalsefalsefalsefalsetruefalsetruenegatedPeriodStartLabel1truefalsefalse-23000000-23[1]USD$falsefalsefalse2truefalsefalse-62000000-62USD$falsefalsefalse3truefalsefalse-260000000-260USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 60 -Paragraph 47 -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. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 310 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6873192&loc=d3e21338-158488 false2Balance, beginning of period6false 5us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpenseus-gaap_truecreditdurationfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse40000004USD$falsefalsefalse2truefalsefalse2500000025USD$falsefalsefalse3truefalsefalse-108000000-108USD$falsefalsefalsexbrli:monetaryItemTypemonetaryTotal of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, charged to costs and expenses.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 09 -Article 12 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e24092-122690 false2(Additions)/Reversals7false 5us-gaap_ValuationAllowancesAndReservesDeductionsus-gaap_truedebitdurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse50000005USD$falsefalsefalse2truefalsefalse1400000014USD$falsefalsefalse3truefalsefalse306000000306USD$falsefalsefalsexbrli:monetaryItemTypemonetaryTotal of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 09 -Article 12 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e24092-122690 false2Deductions8false 5us-gaap_AllowanceForLoanAndLeaseLossesRealEstateus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsetruetruenegatedPeriodEndLabel1truefalsefalse-14000000-14[1]USD$falsetruefalse2truefalsefalse-23000000-23[1]USD$falsetruefalse3truefalsefalse-62000000-62USD$falsetruefalsexbrli:monetaryItemTypemonetaryThe reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 60 -Paragraph 47 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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