2.4.0.82405409 - Disclosure - Investments and Derivative Instruments (Mortgage Loans) (Details)truefalseIn Millions, unless otherwise specifiedfalse1false USDfalsefalse$I2012Q4_hig_ScheduleOfAvailableForSaleSecuritiesTypesOfMortgageLoansAxis_hig_CommercialMemberhttp://www.sec.gov/CIK0000045947instant2012-12-31T00:00:000001-01-01T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$I2011Q4_hig_ScheduleOfAvailableForSaleSecuritiesTypesOfMortgageLoansAxis_hig_CommercialMemberhttp://www.sec.gov/CIK0000045947instant2011-12-31T00:00:000001-01-01T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$3false USDfalsefalse$I2010Q4_hig_ScheduleOfAvailableForSaleSecuritiesTypesOfMortgageLoansAxis_hig_CommercialMemberhttp://www.sec.gov/CIK0000045947instant2010-12-31T00:00:000001-01-01T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$4false USDfalsefalse$I2009Q4_hig_ScheduleOfAvailableForSaleSecuritiesTypesOfMortgageLoansAxis_hig_CommercialMemberhttp://www.sec.gov/CIK0000045947instant2009-12-31T00:00:000001-01-01T00:00:00usdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 4hig_MortgageLoansByMajorTypesAbstracthig_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Mortgage Loans by Major Types2false 5us-gaap_AllowanceForLoanAndLeaseLossesRealEstateus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-14000000-14USD$falsetruefalse2truefalsefalse-23000000-23USD$falsetruefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 60 -Paragraph 47 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 310 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6873192&loc=d3e21338-158488 false2Valuation Allowance3false 5us-gaap_MortgageLoansOnRealEstateCommercialAndConsumerNetus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse49350000004935USD$falsefalsefalse2truefalsefalse41820000004182USD$falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 60 -Paragraph 47 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1(c)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph c -Article 7 true2Carrying Value4false 0truefalsetruefalsefalsefalsefalsefalsefalse1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalse3false USDtruefalse$I2012Q4_hig_ScheduleOfAvailableForSaleSecuritiesTypesOfMortgageLoansAxis_hig_CommercialMemberhttp://www.sec.gov/CIK0000045947instant2012-12-31T00:00:000001-01-01T00:00:00falsefalseCommercial [Member]hig_ScheduleOfAvailableForSaleSecuritiesTypesOfMortgageLoansAxisxbrldihttp://xbrl.org/2006/xbrldihig_CommercialMemberhig_ScheduleOfAvailableForSaleSecuritiesTypesOfMortgageLoansAxisexplicitMemberusdStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$nanafalse0Commercial [Member]5true 4hig_MortgageLoansByMajorTypesAbstracthig_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Mortgage Loans by Major Types6false 5hig_AvailableForSaleSecuritiesMortgageLoansAmortizedCosthig_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseverboseLabel1truefalsefalse49490000004949[1],[2]USD$falsefalsefalse2truefalsefalse42050000004205[1],[2]USD$falsefalsefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryAvailable-for-sale securities mortgage loans amortized cost.No definition available.false2Amortized Cost7false 5us-gaap_AllowanceForLoanAndLeaseLossesRealEstateus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsetruenegatedLabel1truefalsefalse-14000000-14[1]USD$falsefalsefalse2truefalsefalse-23000000-23[1]USD$falsefalsefalse3truefalsefalse-62000000-62USD$falsefalsefalse4truefalsefalse-260000000-260USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 60 -Paragraph 47 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 310 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6873192&loc=d3e21338-158488 false2Valuation Allowance8false 5us-gaap_MortgageLoansOnRealEstateCommercialAndConsumerNetus-gaap_truedebitinstantfalsefalsefalsefalsefalsefalsefalsefalsetotalLabel1truefalsefalse49350000004935[1]USD$falsetruefalse2truefalsefalse41820000004182[1]USD$falsetruefalse3falsefalsefalse00falsefalsefalse4falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryThe balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the 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 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1(c)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph c -Article 7 true2Carrying Value1Includes commercial mortgage loans relating to the sales of the Retirement Plans and Individual Life businesses; see Note 2 - Business Dispositions of Notes to Consolidated Financial Statements for further discussion of this transaction.2Amortized cost represents carrying value prior to valuation allowances, if any.falseInvestments and Derivative Instruments (Mortgage Loans) (Details) (USD $)MillionsUnKnownUnKnownUnKnowntruefalsefalseSheethttp://www.thehartford.com/role/InvestmentsAndDerivativeInstrumentsMortgageLoansDetails48