XML 1123 R82.htm IDEA: XBRL DOCUMENT v2.4.1.9
Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs (Detail) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Available-for-sale Securities | Foreign government  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Fair Value $ 34,147us-gaap_FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_ForeignGovernmentDebtSecuritiesMember
Valuation Technique Matrix pricing
Available-for-sale Securities | Public utilities  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Fair Value 521,199us-gaap_FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= ck0000072499_PublicUtilitiesMember
Valuation Technique Matrix pricing
Available-for-sale Securities | Corporate securities  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Fair Value 5,212,561us-gaap_FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember
Valuation Technique Matrix pricing
Available-for-sale Securities | Collateralized debt obligations  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Fair Value 24,649us-gaap_FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CollateralizedDebtObligationsMember
Valuation Technique Intex discounted cash flows
Available-for-sale Securities | Mortgage-backed securities  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Fair Value 1,332us-gaap_FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_MortgageBackedSecuritiesMember
Valuation Technique Intex discounted cash flows
Available-for-sale Securities | Third Party Pricing Valuation Technique | Collateralized debt obligations  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Fair Value 20,580us-gaap_FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CollateralizedDebtObligationsMember
/ us-gaap_StatementScenarioAxis
= ck0000072499_ThirdPartyPricingValuationTechniqueMember
Valuation Technique Third-Party Vendor
Available-for-sale Securities | Minimum | Foreign government  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Unobservable Input, Option adjusted spread 156ck0000072499_OptionAdjustedSpreadBasisPoints
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_ForeignGovernmentDebtSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
Available-for-sale Securities | Minimum | Public utilities  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Unobservable Input, Option adjusted spread 62ck0000072499_OptionAdjustedSpreadBasisPoints
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= ck0000072499_PublicUtilitiesMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
Available-for-sale Securities | Minimum | Corporate securities  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Unobservable Input, Option adjusted spread 17ck0000072499_OptionAdjustedSpreadBasisPoints
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
Available-for-sale Securities | Minimum | Collateralized debt obligations  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Unobservable Input, Constant prepayment rate 0.00%us-gaap_FairValueInputsPrepaymentRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CollateralizedDebtObligationsMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
Unobservable Input, Annual default rate 0.50%us-gaap_FairValueInputsProbabilityOfDefault
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CollateralizedDebtObligationsMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
Unobservable Input, Loss severity 10.00%us-gaap_FairValueInputsLossSeverity
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CollateralizedDebtObligationsMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
Unobservable Input, Delinquencies 0.00%us-gaap_AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureOtherDelinquencyRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CollateralizedDebtObligationsMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
Unobservable Input, Discount Margin to LIBOR 1.70%us-gaap_FairValueInputsDiscountRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CollateralizedDebtObligationsMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
Available-for-sale Securities | Minimum | Mortgage-backed securities  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Unobservable Input, Constant prepayment rate 2.00%us-gaap_FairValueInputsPrepaymentRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_MortgageBackedSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
Unobservable Input, Annual default rate 20.00%us-gaap_FairValueInputsProbabilityOfDefault
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_MortgageBackedSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
Unobservable Input, Loss severity 55.00%us-gaap_FairValueInputsLossSeverity
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_MortgageBackedSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
Unobservable Input, Delinquencies 5.00%us-gaap_AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureOtherDelinquencyRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_MortgageBackedSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
Unobservable Input, Discount Margin to LIBOR 4.00%us-gaap_FairValueInputsDiscountRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_MortgageBackedSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
Available-for-sale Securities | Maximum | Foreign government  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Unobservable Input, Option adjusted spread 162ck0000072499_OptionAdjustedSpreadBasisPoints
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_ForeignGovernmentDebtSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
Available-for-sale Securities | Maximum | Public utilities  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Unobservable Input, Option adjusted spread 351ck0000072499_OptionAdjustedSpreadBasisPoints
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= ck0000072499_PublicUtilitiesMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
Available-for-sale Securities | Maximum | Corporate securities  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Unobservable Input, Option adjusted spread 725ck0000072499_OptionAdjustedSpreadBasisPoints
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
Available-for-sale Securities | Maximum | Collateralized debt obligations  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Unobservable Input, Constant prepayment rate 25.00%us-gaap_FairValueInputsPrepaymentRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CollateralizedDebtObligationsMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
Unobservable Input, Annual default rate 62.50%us-gaap_FairValueInputsProbabilityOfDefault
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CollateralizedDebtObligationsMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
Unobservable Input, Loss severity 80.00%us-gaap_FairValueInputsLossSeverity
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CollateralizedDebtObligationsMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
Unobservable Input, Delinquencies 32.00%us-gaap_AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureOtherDelinquencyRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CollateralizedDebtObligationsMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
Unobservable Input, Discount Margin to LIBOR 11.00%us-gaap_FairValueInputsDiscountRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CollateralizedDebtObligationsMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
Available-for-sale Securities | Maximum | Mortgage-backed securities  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Unobservable Input, Constant prepayment rate 2.00%us-gaap_FairValueInputsPrepaymentRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_MortgageBackedSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
Unobservable Input, Annual default rate 90.00%us-gaap_FairValueInputsProbabilityOfDefault
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_MortgageBackedSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
Unobservable Input, Loss severity 70.00%us-gaap_FairValueInputsLossSeverity
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_MortgageBackedSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
Unobservable Input, Delinquencies 30.00%us-gaap_AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureOtherDelinquencyRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_MortgageBackedSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
Unobservable Input, Discount Margin to LIBOR 4.30%us-gaap_FairValueInputsDiscountRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_MortgageBackedSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
Available-for-sale Securities | Weighted Average | Foreign government  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Unobservable Input, Option adjusted spread 160ck0000072499_OptionAdjustedSpreadBasisPoints
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_ForeignGovernmentDebtSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
Available-for-sale Securities | Weighted Average | Public utilities  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Unobservable Input, Option adjusted spread 190ck0000072499_OptionAdjustedSpreadBasisPoints
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= ck0000072499_PublicUtilitiesMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
Available-for-sale Securities | Weighted Average | Corporate securities  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Unobservable Input, Option adjusted spread 186ck0000072499_OptionAdjustedSpreadBasisPoints
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
Available-for-sale Securities | Weighted Average | Collateralized debt obligations  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Unobservable Input, Constant prepayment rate 0.50%us-gaap_FairValueInputsPrepaymentRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CollateralizedDebtObligationsMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
Unobservable Input, Annual default rate 1.90%us-gaap_FairValueInputsProbabilityOfDefault
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CollateralizedDebtObligationsMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
Unobservable Input, Loss severity 44.70%us-gaap_FairValueInputsLossSeverity
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CollateralizedDebtObligationsMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
Unobservable Input, Delinquencies 1.00%us-gaap_AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureOtherDelinquencyRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CollateralizedDebtObligationsMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
Unobservable Input, Discount Margin to LIBOR 4.90%us-gaap_FairValueInputsDiscountRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CollateralizedDebtObligationsMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
Available-for-sale Securities | Weighted Average | Mortgage-backed securities  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Unobservable Input, Constant prepayment rate 2.00%us-gaap_FairValueInputsPrepaymentRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_MortgageBackedSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
Unobservable Input, Annual default rate 20.00%us-gaap_FairValueInputsProbabilityOfDefault
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_MortgageBackedSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
Unobservable Input, Loss severity 55.00%us-gaap_FairValueInputsLossSeverity
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_MortgageBackedSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
Unobservable Input, Delinquencies 15.00%us-gaap_AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureOtherDelinquencyRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_MortgageBackedSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
Unobservable Input, Discount Margin to LIBOR 4.30%us-gaap_FairValueInputsDiscountRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_AvailableforsaleSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_MortgageBackedSecuritiesMember
/ us-gaap_RangeAxis
= us-gaap_WeightedAverageMember
Derivative Assets | Collateralized debt obligations  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Fair Value 3,669us-gaap_FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_DerivativeFinancialInstrumentsAssetsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_CollateralizedDebtObligationsMember
Valuation Technique Discounted cash flow
Unobservable Input, Constant prepayment rate    [1]
Derivative Assets | Total Return Swap  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Fair Value 7,914us-gaap_FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_DerivativeFinancialInstrumentsAssetsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_TotalReturnSwapMember
Valuation Technique Third-Party Vendor
Unobservable Input, Spread and discount rates    [1]
Derivative liability | Total Return Swap  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Fair Value (757)us-gaap_FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= us-gaap_DerivativeFinancialInstrumentsLiabilitiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_TotalReturnSwapMember
Valuation Technique Third-Party Vendor
Unobservable Input, Spread and discount rates    [1]
Reserve at Fair Value | MVLO  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Fair Value 14,903,758us-gaap_FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= ck0000072499_ReserveMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= ck0000072499_MarketValueLiabilityOptionsMember
Valuation Technique Discounted cash flow
Unobservable Input, Annuitizations, minimum 0.00%us-gaap_StructuredSettlementAnnuitiesInterestRateLowEnd
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= ck0000072499_ReserveMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= ck0000072499_MarketValueLiabilityOptionsMember
Unobservable Input, Annuitizations, maximum 25.00%us-gaap_StructuredSettlementAnnuitiesInterestRateHighEnd
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= ck0000072499_ReserveMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= ck0000072499_MarketValueLiabilityOptionsMember
Unobservable Input, Mortality, minimum 0.00%us-gaap_LongDurationContractsAssumptionsByProductAndGuaranteeMortalityRateLowEnd
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= ck0000072499_ReserveMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= ck0000072499_MarketValueLiabilityOptionsMember
Unobservable Input, Mortality, maximum 100.00%us-gaap_LongDurationContractsAssumptionsByProductAndGuaranteeMortalityRateHighEnd
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= ck0000072499_ReserveMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= ck0000072499_MarketValueLiabilityOptionsMember
Reserve at Fair Value | GMWB and GMAB  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Fair Value $ 1,756,137us-gaap_FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= ck0000072499_ReserveMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= ck0000072499_GuaranteedMinimumWithdrawalBenefitAndGuaranteedMinimumAccumulationBenefitMember
Valuation Technique Discounted cash flow
Unobservable Input, Mortality, minimum 0.00%us-gaap_LongDurationContractsAssumptionsByProductAndGuaranteeMortalityRateLowEnd
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= ck0000072499_ReserveMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= ck0000072499_GuaranteedMinimumWithdrawalBenefitAndGuaranteedMinimumAccumulationBenefitMember
Unobservable Input, Mortality, maximum 100.00%us-gaap_LongDurationContractsAssumptionsByProductAndGuaranteeMortalityRateHighEnd
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= ck0000072499_ReserveMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= ck0000072499_GuaranteedMinimumWithdrawalBenefitAndGuaranteedMinimumAccumulationBenefitMember
Reserve at Fair Value | Minimum | MVLO  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Unobservable Input, Surrenders 0.00%us-gaap_CorporateLifeInsuranceGuaranteedRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= ck0000072499_ReserveMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= ck0000072499_MarketValueLiabilityOptionsMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
Unobservable Input, Withdrawal Benefit Election 0.00%ck0000072499_FairValueInputsWithdrawalBenefitElection
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= ck0000072499_ReserveMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= ck0000072499_MarketValueLiabilityOptionsMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
Reserve at Fair Value | Minimum | GMWB and GMAB  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Unobservable Input, Surrenders 0.50%us-gaap_CorporateLifeInsuranceGuaranteedRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= ck0000072499_ReserveMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= ck0000072499_GuaranteedMinimumWithdrawalBenefitAndGuaranteedMinimumAccumulationBenefitMember
/ us-gaap_RangeAxis
= us-gaap_MinimumMember
Reserve at Fair Value | Maximum | MVLO  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Unobservable Input, Surrenders 25.00%us-gaap_CorporateLifeInsuranceGuaranteedRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= ck0000072499_ReserveMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= ck0000072499_MarketValueLiabilityOptionsMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
Unobservable Input, Withdrawal Benefit Election 50.00%ck0000072499_FairValueInputsWithdrawalBenefitElection
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= ck0000072499_ReserveMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= ck0000072499_MarketValueLiabilityOptionsMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
Reserve at Fair Value | Maximum | GMWB and GMAB  
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]  
Unobservable Input, Surrenders 35.00%us-gaap_CorporateLifeInsuranceGuaranteedRate
/ us-gaap_EligibleItemOrGroupForFairValueOptionAxis
= ck0000072499_ReserveMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= ck0000072499_GuaranteedMinimumWithdrawalBenefitAndGuaranteedMinimumAccumulationBenefitMember
/ us-gaap_RangeAxis
= us-gaap_MaximumMember
[1] Management does not have insight into the specific assumptions used. See narrative below for qualitative discussion.