Toggle SGML Header (+)


Section 1: 10-Q (10-Q)

Document
500000018000000190000007000000126000000338000000129000000145000000970000003940000001820000002010000005670000005830000001560000002490000005690000005990000008940000006210000001970000001960000004070000000175740000001590000006040000001351000000false--12-31Q320190001527469250000002800000025000000220000006002500000014620000000.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.0010.00171000005000000750000075000004250000003250000007100000500000075000007500000425000000325000000340000080000010000004100000162400000254000003300000800000100000040000001501000002540000034000008000001000000410000016240000025400000330000080000010000004000000150100000254000000057000000110000000804000000655000000100000033700000035000000347000000300000002300000012000000170000002720000001000000101800000070000001930000003690000001550000004720000007700000095000000130000003000000114000000126100000054000000223000000140000001900000014000000420000008800000025700000012700000031300000021730000001259000000236900000014740000003200000028000000110000003000000300000070000005190000008000000020000000500000060000001200000093400000018000000050000001000000200000030000002270000003800000030000000700000090000001900000014110000002280000001500000039000000200000005600000035700000020000002200000027000000100000003000000052000000640000005900000085000000100000009000000150000000078400000010650000001400000016000000024300000038900000036600000012100000000600000058000000638000000700000002670000008901000000168500000001141500000015693000000008630000003450000000.000.000000000000004100000062300000051000000173000000140000000130000000040000001200000001010000003000000032000000162000000010300000084000000344000000320000000143000000332000000350000001000000Includes cash and cash equivalents, restricted cash, and cash and cash equivalents of consolidated variable interest entities. 0001527469 2019-01-01 2019-09-30 0001527469 ahl:CommonClassM4Member 2019-09-30 0001527469 us-gaap:CommonClassBMember 2019-09-30 0001527469 ahl:CommonClassM3Member 2019-09-30 0001527469 ahl:CommonClassM1Member 2019-09-30 0001527469 ahl:CommonClassM2Member 2019-09-30 0001527469 us-gaap:CommonClassAMember 2019-09-30 0001527469 us-gaap:CommonClassAMember 2019-01-01 2019-09-30 0001527469 us-gaap:SeriesAPreferredStockMember 2019-01-01 2019-09-30 0001527469 us-gaap:SeriesBPreferredStockMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember 2019-09-30 0001527469 us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember 2019-09-30 0001527469 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember srt:AffiliatedEntityMember 2018-12-31 0001527469 2018-12-31 0001527469 srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-12-31 0001527469 us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-12-31 0001527469 ahl:CommonClassM2Member 2018-12-31 0001527469 us-gaap:CommonClassBMember 2018-12-31 0001527469 ahl:CommonClassM4Member 2018-12-31 0001527469 us-gaap:CommonClassAMember 2018-12-31 0001527469 ahl:CommonClassM1Member 2018-12-31 0001527469 us-gaap:SeriesAPreferredStockMember 2018-12-31 0001527469 us-gaap:SeriesBPreferredStockMember 2019-09-30 0001527469 us-gaap:SeriesAPreferredStockMember 2019-09-30 0001527469 ahl:CommonClassM3Member 2018-12-31 0001527469 us-gaap:SeriesBPreferredStockMember 2018-12-31 0001527469 srt:ParentCompanyMember ahl:CommonClassM4Member 2018-12-31 0001527469 srt:ParentCompanyMember ahl:CommonClassM2Member 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ParentCompanyMember us-gaap:CommonClassBMember 2018-12-31 0001527469 srt:ParentCompanyMember ahl:CommonClassM4Member 2019-09-30 0001527469 srt:ParentCompanyMember ahl:CommonClassM3Member 2019-09-30 0001527469 srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ParentCompanyMember us-gaap:CommonClassAMember 2018-12-31 0001527469 us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-12-31 0001527469 srt:ParentCompanyMember ahl:CommonClassM3Member 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ParentCompanyMember us-gaap:CommonClassAMember 2019-09-30 0001527469 us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 srt:ParentCompanyMember ahl:CommonClassM1Member 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 srt:ParentCompanyMember ahl:CommonClassM2Member 2018-12-31 0001527469 srt:ParentCompanyMember ahl:CommonClassM1Member 2019-09-30 0001527469 srt:ParentCompanyMember us-gaap:CommonClassBMember 2019-09-30 0001527469 srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember 2018-01-01 2018-09-30 0001527469 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember 2019-07-01 2019-09-30 0001527469 2018-07-01 2018-09-30 0001527469 ahl:CommonClassM4Member 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember 2019-01-01 2019-09-30 0001527469 us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-07-01 2019-09-30 0001527469 2019-07-01 2019-09-30 0001527469 ahl:CommonClassM4Member 2018-01-01 2018-09-30 0001527469 us-gaap:CommonClassBMember 2018-01-01 2018-09-30 0001527469 ahl:CommonClassM2Member 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember 2018-07-01 2018-09-30 0001527469 ahl:CommonClassM1Member 2019-07-01 2019-09-30 0001527469 us-gaap:CommonClassBMember 2019-01-01 2019-09-30 0001527469 us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-01-01 2018-09-30 0001527469 us-gaap:CommonClassAMember 2018-01-01 2018-09-30 0001527469 us-gaap:CommonClassBMember 2019-07-01 2019-09-30 0001527469 us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-01-01 2019-09-30 0001527469 ahl:CommonClassM1Member 2018-07-01 2018-09-30 0001527469 ahl:CommonClassM4Member 2019-01-01 2019-09-30 0001527469 us-gaap:CommonClassAMember 2019-07-01 2019-09-30 0001527469 us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-07-01 2018-09-30 0001527469 ahl:CommonClassM2Member 2018-01-01 2018-09-30 0001527469 ahl:CommonClassM2Member 2019-01-01 2019-09-30 0001527469 ahl:CommonClassM1Member 2018-01-01 2018-09-30 0001527469 us-gaap:CommonClassBMember 2018-07-01 2018-09-30 0001527469 ahl:CommonClassM3Member 2018-01-01 2018-09-30 0001527469 us-gaap:CommonClassAMember 2018-07-01 2018-09-30 0001527469 ahl:CommonClassM4Member 2018-07-01 2018-09-30 0001527469 ahl:CommonClassM3Member 2019-01-01 2019-09-30 0001527469 ahl:CommonClassM3Member 2018-07-01 2018-09-30 0001527469 ahl:CommonClassM3Member 2019-07-01 2019-09-30 0001527469 ahl:CommonClassM1Member 2019-01-01 2019-09-30 0001527469 ahl:CommonClassM2Member 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember srt:AffiliatedEntityMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember srt:AffiliatedEntityMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember srt:AffiliatedEntityMember 2019-07-01 2019-09-30 0001527469 srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember srt:AffiliatedEntityMember 2019-01-01 2019-09-30 0001527469 srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-07-01 2019-09-30 0001527469 srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-07-01 2018-09-30 0001527469 srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-01-01 2018-09-30 0001527469 us-gaap:AdditionalPaidInCapitalMember 2018-01-01 2018-09-30 0001527469 us-gaap:RetainedEarningsMember 2018-01-01 2018-09-30 0001527469 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2018-01-01 0001527469 us-gaap:AdditionalPaidInCapitalMember 2017-12-31 0001527469 us-gaap:RetainedEarningsMember 2017-12-31 0001527469 us-gaap:RetainedEarningsMember 2019-01-01 2019-09-30 0001527469 2018-01-01 0001527469 us-gaap:RetainedEarningsMember 2018-12-31 0001527469 2018-09-30 0001527469 us-gaap:AdditionalPaidInCapitalMember 2019-09-30 0001527469 us-gaap:PreferredStockMember 2019-01-01 2019-09-30 0001527469 us-gaap:CommonStockMember 2017-12-31 0001527469 us-gaap:CommonStockMember 2018-12-31 0001527469 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2018-09-30 0001527469 us-gaap:CommonStockMember 2019-09-30 0001527469 us-gaap:RetainedEarningsMember 2019-09-30 0001527469 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2019-01-01 2019-09-30 0001527469 us-gaap:AdditionalPaidInCapitalMember 2018-09-30 0001527469 us-gaap:CommonStockMember us-gaap:AdditionalPaidInCapitalMember 2018-01-01 2018-09-30 0001527469 us-gaap:RetainedEarningsMember 2018-09-30 0001527469 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2018-01-01 2018-09-30 0001527469 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2018-12-31 0001527469 us-gaap:PreferredStockMember 2018-12-31 0001527469 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2019-09-30 0001527469 us-gaap:CommonStockMember us-gaap:AdditionalPaidInCapitalMember 2019-01-01 2019-09-30 0001527469 us-gaap:PreferredStockMember 2019-09-30 0001527469 us-gaap:PreferredStockMember 2017-12-31 0001527469 us-gaap:PreferredStockMember 2018-09-30 0001527469 us-gaap:AdditionalPaidInCapitalMember 2018-12-31 0001527469 us-gaap:PreferredStockMember us-gaap:AdditionalPaidInCapitalMember 2019-01-01 2019-09-30 0001527469 us-gaap:CommonStockMember 2019-01-01 2019-09-30 0001527469 us-gaap:RetainedEarningsMember 2018-01-01 0001527469 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2017-12-31 0001527469 us-gaap:AdditionalPaidInCapitalMember 2019-01-01 2019-09-30 0001527469 us-gaap:CommonStockMember 2018-09-30 0001527469 2017-12-31 0001527469 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2018-06-30 0001527469 us-gaap:CommonStockMember 2018-06-30 0001527469 us-gaap:RetainedEarningsMember 2019-07-01 2019-09-30 0001527469 us-gaap:RetainedEarningsMember 2019-06-30 0001527469 2019-06-30 0001527469 2018-06-30 0001527469 us-gaap:CommonStockMember 2019-07-01 2019-09-30 0001527469 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2019-07-01 2019-09-30 0001527469 us-gaap:CommonStockMember us-gaap:AdditionalPaidInCapitalMember 2018-07-01 2018-09-30 0001527469 us-gaap:AdditionalPaidInCapitalMember 2018-06-30 0001527469 us-gaap:AdditionalPaidInCapitalMember 2019-07-01 2019-09-30 0001527469 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2018-07-01 2018-09-30 0001527469 us-gaap:AdditionalPaidInCapitalMember 2019-06-30 0001527469 us-gaap:PreferredStockMember us-gaap:AdditionalPaidInCapitalMember 2019-07-01 2019-09-30 0001527469 us-gaap:PreferredStockMember 2019-07-01 2019-09-30 0001527469 us-gaap:RetainedEarningsMember 2018-07-01 2018-09-30 0001527469 us-gaap:PreferredStockMember 2018-06-30 0001527469 us-gaap:AdditionalPaidInCapitalMember 2018-07-01 2018-09-30 0001527469 us-gaap:CommonStockMember us-gaap:AdditionalPaidInCapitalMember 2019-07-01 2019-09-30 0001527469 us-gaap:CommonStockMember 2019-06-30 0001527469 us-gaap:RetainedEarningsMember 2018-06-30 0001527469 us-gaap:PreferredStockMember 2019-06-30 0001527469 us-gaap:AccumulatedOtherComprehensiveIncomeMember 2019-06-30 0001527469 ahl:ReinsuranceSettlementsMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember 2018-01-01 2018-09-30 0001527469 srt:AffiliatedEntityMember 2019-01-01 2019-09-30 0001527469 ahl:InvestmentFundsMember us-gaap:ExchangeOfStockForStockMember 2019-01-01 2019-09-30 0001527469 ahl:InvestmentFundsMember us-gaap:ExchangeOfStockForStockMember 2018-01-01 2018-09-30 0001527469 ahl:ReinsuranceSettlementsMember srt:AffiliatedEntityMember 2018-01-01 2018-09-30 0001527469 srt:AffiliatedEntityMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember 2019-01-01 2019-09-30 0001527469 ahl:ReinsuranceSettlementsMember 2019-01-01 2019-09-30 0001527469 ahl:ReinsuranceSettlementsMember srt:AffiliatedEntityMember 2019-01-01 2019-09-30 0001527469 ahl:PensionRiskTransferPremiumsMember 2018-01-01 2018-09-30 0001527469 ahl:PensionRiskTransferPremiumsMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember srt:AffiliatedEntityMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember srt:AffiliatedEntityMember 2018-01-01 2018-09-30 0001527469 srt:MinimumMember srt:ScenarioForecastMember us-gaap:AccountingStandardsUpdate201613Member us-gaap:RetainedEarningsMember 2020-01-01 2020-01-01 0001527469 srt:MaximumMember srt:ScenarioForecastMember us-gaap:AccountingStandardsUpdate201613Member us-gaap:RetainedEarningsMember 2020-01-01 2020-01-01 0001527469 srt:MinimumMember srt:ScenarioForecastMember us-gaap:AccountingStandardsUpdate201613Member us-gaap:CommercialRealEstatePortfolioSegmentMember 2020-01-01 0001527469 srt:MaximumMember srt:ScenarioForecastMember us-gaap:AccountingStandardsUpdate201613Member us-gaap:CommercialRealEstatePortfolioSegmentMember 2020-01-01 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember 2018-06-30 0001527469 us-gaap:CommercialRealEstatePortfolioSegmentMember ahl:CommercialMortgageLoansExcludingLoansUnderDevelopmentMember ahl:LTV50to60PercentMember 2019-09-30 0001527469 us-gaap:CommercialRealEstatePortfolioSegmentMember ahl:CommercialMortgageLoansExcludingLoansUnderDevelopmentMember 2019-09-30 0001527469 us-gaap:CommercialRealEstatePortfolioSegmentMember ahl:CommercialMortgageLoansExcludingLoansUnderDevelopmentMember ahl:LTV81to100PercentMember 2018-12-31 0001527469 us-gaap:CommercialRealEstatePortfolioSegmentMember ahl:CommercialMortgageLoansExcludingLoansUnderDevelopmentMember 2018-12-31 0001527469 us-gaap:CommercialRealEstatePortfolioSegmentMember ahl:CommercialMortgageLoansExcludingLoansUnderDevelopmentMember ahl:LTVLessThan50PercentMember 2018-12-31 0001527469 us-gaap:CommercialRealEstatePortfolioSegmentMember ahl:CommercialMortgageLoansExcludingLoansUnderDevelopmentMember ahl:LTVLessThan50PercentMember 2019-09-30 0001527469 us-gaap:CommercialRealEstatePortfolioSegmentMember ahl:CommercialMortgageLoansExcludingLoansUnderDevelopmentMember ahl:LTV61to70PercentMember 2019-09-30 0001527469 us-gaap:CommercialRealEstatePortfolioSegmentMember ahl:CommercialMortgageLoansExcludingLoansUnderDevelopmentMember ahl:LTV71to80PercentMember 2019-09-30 0001527469 us-gaap:CommercialRealEstatePortfolioSegmentMember ahl:CommercialMortgageLoansExcludingLoansUnderDevelopmentMember ahl:LTV81to100PercentMember 2019-09-30 0001527469 us-gaap:CommercialRealEstatePortfolioSegmentMember ahl:CommercialMortgageLoansExcludingLoansUnderDevelopmentMember ahl:LTV61to70PercentMember 2018-12-31 0001527469 us-gaap:CommercialRealEstatePortfolioSegmentMember ahl:CommercialMortgageLoansExcludingLoansUnderDevelopmentMember ahl:LTV71to80PercentMember 2018-12-31 0001527469 us-gaap:CommercialRealEstatePortfolioSegmentMember ahl:CommercialMortgageLoansExcludingLoansUnderDevelopmentMember ahl:LTV50to60PercentMember 2018-12-31 0001527469 ahl:DebtServiceCoverageRatioGreaterthan1.20Member us-gaap:CommercialRealEstatePortfolioSegmentMember ahl:CommercialMortgageLoansExcludingLoansUnderDevelopmentMember 2018-12-31 0001527469 ahl:DebtServiceCoverageRatioLessthan1.00Member us-gaap:CommercialRealEstatePortfolioSegmentMember ahl:CommercialMortgageLoansExcludingLoansUnderDevelopmentMember 2019-09-30 0001527469 ahl:DebtServiceCoverageRatio1.00to1.20Member us-gaap:CommercialRealEstatePortfolioSegmentMember ahl:CommercialMortgageLoansExcludingLoansUnderDevelopmentMember 2019-09-30 0001527469 ahl:DebtServiceCoverageRatioLessthan1.00Member us-gaap:CommercialRealEstatePortfolioSegmentMember ahl:CommercialMortgageLoansExcludingLoansUnderDevelopmentMember 2018-12-31 0001527469 ahl:DebtServiceCoverageRatioGreaterthan1.20Member us-gaap:CommercialRealEstatePortfolioSegmentMember ahl:CommercialMortgageLoansExcludingLoansUnderDevelopmentMember 2019-09-30 0001527469 ahl:DebtServiceCoverageRatio1.00to1.20Member us-gaap:CommercialRealEstatePortfolioSegmentMember ahl:CommercialMortgageLoansExcludingLoansUnderDevelopmentMember 2018-12-31 0001527469 stpr:TX ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:ResidentialPortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:ResidentialPortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 country:IE ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:ResidentialPortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 stpr:TX ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:ResidentialPortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 ahl:OtherU.S.StatesMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:ResidentialPortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 country:US ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:ResidentialPortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 ahl:OtherU.S.StatesMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:ResidentialPortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 country:US ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:ResidentialPortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 stpr:CA ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:ResidentialPortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 stpr:FL ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:ResidentialPortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 stpr:NY ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:ResidentialPortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 country:IE ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:ResidentialPortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 stpr:NY ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:ResidentialPortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 stpr:FL ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:ResidentialPortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 stpr:CA ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:ResidentialPortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:ResidentialPortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AthoraHoldingLtd.Member us-gaap:PrivateEquityFundsMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:OtherFundMember srt:AffiliatedEntityMember 2019-09-30 0001527469 us-gaap:RealEstateFundsMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:CreditFundsMember srt:AffiliatedEntityMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember ahl:OtherFundMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:VenerableHoldingsInc.Member us-gaap:PrivateEquityFundsMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AthoraHoldingLtd.Member us-gaap:PrivateEquityFundsMember srt:AffiliatedEntityMember 2018-12-31 0001527469 ahl:RealAssetsMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:RealEstateFundsMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:PrivateEquityFundsMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:DifferentiatedInvestmentsMember srt:AffiliatedEntityMember 2018-12-31 0001527469 us-gaap:RealEstateFundsMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember ahl:RealAssetsMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AmeriHomeMember us-gaap:PrivateEquityFundsMember srt:AffiliatedEntityMember 2018-12-31 0001527469 ahl:CreditFundsMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:RealEstateFundsMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:PrivateEquityFundsMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:PrivateEquityFundsMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:DifferentiatedInvestmentsMember srt:AffiliatedEntityMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember ahl:CreditFundsMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:CommoditiesInvestmentMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:VenerableHoldingsInc.Member us-gaap:PrivateEquityFundsMember srt:AffiliatedEntityMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember ahl:CreditFundsMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:CommoditiesInvestmentMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AmeriHomeMember us-gaap:PrivateEquityFundsMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:CreditFundsMember srt:AffiliatedEntityMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember ahl:RealAssetsMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:CatalinaHoldingsBermudaLtdMember us-gaap:PrivateEquityFundsMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CommoditiesInvestmentMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:RealAssetsMember srt:AffiliatedEntityMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:PrivateEquityFundsMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:RealAssetsMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:CatalinaHoldingsBermudaLtdMember us-gaap:PrivateEquityFundsMember srt:AffiliatedEntityMember 2019-09-30 0001527469 ahl:RealAssetsMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CommoditiesInvestmentMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:OtherFundMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:RealEstateFundsMember srt:AffiliatedEntityMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember ahl:OtherFundMember 2018-12-31 0001527469 ahl:CreditFundsMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:RealEstateFundsMember srt:AffiliatedEntityMember 2019-09-30 0001527469 us-gaap:ResidentialPortfolioSegmentMember 2018-12-31 0001527469 us-gaap:CommercialRealEstatePortfolioSegmentMember ahl:CommercialMortgageLoansUnderDevelopmentMember 2018-12-31 0001527469 us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 0001527469 us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 0001527469 us-gaap:ResidentialPortfolioSegmentMember 2019-09-30 0001527469 us-gaap:CommercialRealEstatePortfolioSegmentMember ahl:CommercialMortgageLoansUnderDevelopmentMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:CollateralizedDebtObligationsMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:USStatesAndPoliticalSubdivisionsMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:CommercialMortgageBackedSecuritiesMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:USTreasuryAndGovernmentMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:CorporateDebtSecuritiesMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:AssetBackedSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember srt:AffiliatedEntityMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:ResidentialMortgageBackedSecuritiesMember 2019-09-30 0001527469 ahl:U.S.SouthAtlanticMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 0001527469 srt:IndustrialPropertyMember ahl:MortgageLoansNetMember ahl:PropertyTypeConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 ahl:U.S.EastSouthCentralMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 country:US ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 ahl:U.S.PacificMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 srt:OfficeBuildingMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 0001527469 ahl:U.S.WestNorthCentralMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 0001527469 ahl:U.S.SouthAtlanticMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 srt:HotelMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 0001527469 srt:OtherPropertyMember ahl:MortgageLoansNetMember ahl:PropertyTypeConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 ahl:U.S.MiddleAtlanticMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 ahl:U.S.MiddleAtlanticMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 0001527469 ahl:U.S.WestNorthCentralMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 0001527469 country:US ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 ahl:U.SEastNorthCentralMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 0001527469 ahl:MortgageLoansNetMember ahl:PropertyTypeConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 srt:OtherPropertyMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 0001527469 srt:RetailSiteMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 0001527469 srt:OfficeBuildingMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 0001527469 srt:RetailSiteMember ahl:MortgageLoansNetMember ahl:PropertyTypeConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 srt:ApartmentBuildingMember ahl:MortgageLoansNetMember ahl:PropertyTypeConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 country:US us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 0001527469 ahl:U.S.PacificMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 0001527469 srt:RetailSiteMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 0001527469 us-gaap:NonUsMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 srt:OfficeBuildingMember ahl:MortgageLoansNetMember ahl:PropertyTypeConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 ahl:U.S.WestNorthCentralMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 srt:HotelMember ahl:MortgageLoansNetMember ahl:PropertyTypeConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 ahl:U.SEastNorthCentralMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 0001527469 srt:ApartmentBuildingMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 0001527469 ahl:U.S.EastSouthCentralMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 0001527469 ahl:U.S.MountainMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 ahl:U.SEastNorthCentralMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 ahl:U.S.MiddleAtlanticMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 ahl:U.S.WestSouthCentralMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 ahl:U.S.PacificMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 ahl:U.S.WestNorthCentralMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 ahl:U.S.EastSouthCentralMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 ahl:U.S.MountainMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 0001527469 srt:OtherPropertyMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 0001527469 ahl:U.S.WestSouthCentralMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 0001527469 ahl:U.S.NewEnglandMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 0001527469 ahl:U.S.WestSouthCentralMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 0001527469 srt:IndustrialPropertyMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 0001527469 srt:IndustrialPropertyMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 0001527469 ahl:U.S.MountainMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 0001527469 country:US us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 0001527469 srt:HotelMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 0001527469 ahl:U.S.EastSouthCentralMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 0001527469 ahl:U.S.MountainMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 srt:ApartmentBuildingMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 0001527469 ahl:U.S.WestSouthCentralMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 ahl:MortgageLoansNetMember ahl:PropertyTypeConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 ahl:U.S.PacificMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 0001527469 ahl:U.S.NewEnglandMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 ahl:U.SEastNorthCentralMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 srt:OfficeBuildingMember ahl:MortgageLoansNetMember ahl:PropertyTypeConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 ahl:U.S.SouthAtlanticMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 us-gaap:NonUsMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 srt:ApartmentBuildingMember ahl:MortgageLoansNetMember ahl:PropertyTypeConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 ahl:U.S.NewEnglandMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 0001527469 us-gaap:NonUsMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 0001527469 ahl:U.S.NewEnglandMember ahl:MortgageLoansNetMember us-gaap:GeographicConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 srt:OtherPropertyMember ahl:MortgageLoansNetMember ahl:PropertyTypeConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 srt:RetailSiteMember ahl:MortgageLoansNetMember ahl:PropertyTypeConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 2018-12-31 0001527469 ahl:U.S.MiddleAtlanticMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 0001527469 srt:IndustrialPropertyMember ahl:MortgageLoansNetMember ahl:PropertyTypeConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 ahl:U.S.SouthAtlanticMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 0001527469 srt:HotelMember ahl:MortgageLoansNetMember ahl:PropertyTypeConcentrationRiskMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2019-09-30 2019-09-30 0001527469 us-gaap:NonUsMember us-gaap:CommercialRealEstatePortfolioSegmentMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:DebtSecuritiesTradingMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:DebtSecuritiesTradingMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:MortgagesMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:OtherInvestmentsMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:DebtSecuritiesTradingMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:OtherInvestmentsMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:DebtSecuritiesTradingMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:DebtSecuritiesAvailableforsaleMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:MortgagesMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:MortgagesMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:MortgagesMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:DebtSecuritiesAvailableforsaleMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:OtherInvestmentsMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:FundsWithheldatInterestMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:DebtSecuritiesAvailableforsaleMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:DebtSecuritiesAvailableforsaleMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:FundsWithheldatInterestMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:FundsWithheldatInterestMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:OtherInvestmentsMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:FundsWithheldatInterestMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2018-12-31 0001527469 us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:DebtSecuritiesMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember ahl:InvestmentFundsMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2019-09-30 0001527469 us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:DebtSecuritiesMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:DebtSecuritiesMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2019-09-30 0001527469 ahl:InvestmentFundsMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2019-09-30 0001527469 ahl:InvestmentFundsMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:DebtSecuritiesMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember ahl:InvestmentFundsMember us-gaap:VariableInterestEntityNotPrimaryBeneficiaryMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:USStatesAndPoliticalSubdivisionsMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:CorporateDebtSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember srt:AffiliatedEntityMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:CommercialMortgageBackedSecuritiesMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:ForeignGovernmentDebtSecuritiesMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:CollateralizedDebtObligationsMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:USTreasuryAndGovernmentMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember srt:AffiliatedEntityMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:ResidentialMortgageBackedSecuritiesMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:AssetBackedSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember srt:AffiliatedEntityMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember srt:AffiliatedEntityMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember srt:AffiliatedEntityMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:CorporateDebtSecuritiesMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:USStatesAndPoliticalSubdivisionsMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:AssetBackedSecuritiesMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:CollateralizedDebtObligationsMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2018-12-31 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:USTreasuryAndGovernmentMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2018-12-31 0001527469 us-gaap:FixedMaturitiesMember 2018-12-31 0001527469 us-gaap:FixedMaturitiesMember 2019-09-30 0001527469 us-gaap:MortgagesMember 2018-12-31 0001527469 us-gaap:MortgagesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:DebtSecuritiesMember srt:AffiliatedEntityMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember srt:AffiliatedEntityMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember srt:AffiliatedEntityMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:ForeignGovernmentDebtSecuritiesMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:USStatesAndPoliticalSubdivisionsMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:ForeignGovernmentDebtSecuritiesMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:CollateralizedDebtObligationsMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:DebtSecuritiesMember srt:AffiliatedEntityMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:USTreasuryAndGovernmentMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:CorporateDebtSecuritiesMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember srt:AffiliatedEntityMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2019-09-30 0001527469 ahl:ConsolidatedEntityExcludingVariableInterestEntitiesVIEandInvestmentsinRelatedPartyMember us-gaap:AssetBackedSecuritiesMember us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2019-09-30 0001527469 us-gaap:ForeignExchangeForwardMember us-gaap:FairValueHedgingMember us-gaap:DesignatedAsHedgingInstrumentMember 2019-07-01 2019-09-30 0001527469 us-gaap:ForeignExchangeForwardMember us-gaap:FairValueHedgingMember us-gaap:DesignatedAsHedgingInstrumentMember 2019-01-01 2019-09-30 0001527469 us-gaap:ForeignExchangeForwardMember us-gaap:FairValueHedgingMember us-gaap:DesignatedAsHedgingInstrumentMember 2018-12-31 0001527469 us-gaap:CurrencySwapMember us-gaap:CashFlowHedgingMember us-gaap:DesignatedAsHedgingInstrumentMember 2019-01-01 2019-09-30 0001527469 us-gaap:CurrencySwapMember us-gaap:CashFlowHedgingMember us-gaap:DesignatedAsHedgingInstrumentMember 2018-01-01 2018-09-30 0001527469 us-gaap:ForeignExchangeForwardMember us-gaap:FairValueHedgingMember us-gaap:DesignatedAsHedgingInstrumentMember 2019-09-30 0001527469 us-gaap:CurrencySwapMember us-gaap:CashFlowHedgingMember us-gaap:DesignatedAsHedgingInstrumentMember 2019-07-01 2019-09-30 0001527469 us-gaap:CurrencySwapMember us-gaap:CashFlowHedgingMember us-gaap:DesignatedAsHedgingInstrumentMember 2018-07-01 2018-09-30 0001527469 us-gaap:ForeignExchangeForwardMember us-gaap:GainLossOnInvestmentsMember1 2018-01-01 2018-09-30 0001527469 us-gaap:FutureMember us-gaap:GainLossOnInvestmentsMember1 2019-01-01 2019-09-30 0001527469 us-gaap:StockOptionMember us-gaap:GainLossOnInvestmentsMember1 2018-07-01 2018-09-30 0001527469 us-gaap:GainLossOnInvestmentsMember1 2018-01-01 2018-09-30 0001527469 us-gaap:SwapMember us-gaap:GainLossOnInvestmentsMember1 2019-01-01 2019-09-30 0001527469 us-gaap:SwapMember us-gaap:GainLossOnInvestmentsMember1 2018-07-01 2018-09-30 0001527469 us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:InterestSensitiveContractBenefitsMember 2018-01-01 2018-09-30 0001527469 us-gaap:GainLossOnInvestmentsMember1 2019-01-01 2019-09-30 0001527469 us-gaap:SwapMember us-gaap:GainLossOnInvestmentsMember1 2019-07-01 2019-09-30 0001527469 us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:InterestSensitiveContractBenefitsMember 2019-07-01 2019-09-30 0001527469 us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:GainLossOnInvestmentsMember1 2018-01-01 2018-09-30 0001527469 us-gaap:FutureMember us-gaap:GainLossOnInvestmentsMember1 2018-07-01 2018-09-30 0001527469 us-gaap:ForeignExchangeForwardMember us-gaap:GainLossOnInvestmentsMember1 2019-01-01 2019-09-30 0001527469 us-gaap:GainLossOnInvestmentsMember1 2019-07-01 2019-09-30 0001527469 us-gaap:StockOptionMember us-gaap:GainLossOnInvestmentsMember1 2018-01-01 2018-09-30 0001527469 us-gaap:ForeignExchangeForwardMember us-gaap:GainLossOnInvestmentsMember1 2019-07-01 2019-09-30 0001527469 us-gaap:SwapMember us-gaap:GainLossOnInvestmentsMember1 2018-01-01 2018-09-30 0001527469 us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:InterestSensitiveContractBenefitsMember 2019-01-01 2019-09-30 0001527469 us-gaap:GainLossOnInvestmentsMember1 2018-07-01 2018-09-30 0001527469 us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:GainLossOnInvestmentsMember1 2018-07-01 2018-09-30 0001527469 us-gaap:StockOptionMember us-gaap:GainLossOnInvestmentsMember1 2019-07-01 2019-09-30 0001527469 us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:InterestSensitiveContractBenefitsMember 2018-07-01 2018-09-30 0001527469 us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:GainLossOnInvestmentsMember1 2019-07-01 2019-09-30 0001527469 us-gaap:StockOptionMember us-gaap:GainLossOnInvestmentsMember1 2019-01-01 2019-09-30 0001527469 us-gaap:FutureMember us-gaap:GainLossOnInvestmentsMember1 2019-07-01 2019-09-30 0001527469 us-gaap:FutureMember us-gaap:GainLossOnInvestmentsMember1 2018-01-01 2018-09-30 0001527469 us-gaap:ForeignExchangeForwardMember us-gaap:GainLossOnInvestmentsMember1 2018-07-01 2018-09-30 0001527469 us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:GainLossOnInvestmentsMember1 2019-01-01 2019-09-30 0001527469 us-gaap:CreditDefaultSwapMember us-gaap:NondesignatedMember 2019-09-30 0001527469 us-gaap:CurrencySwapMember us-gaap:DesignatedAsHedgingInstrumentMember 2019-09-30 0001527469 us-gaap:StockOptionMember us-gaap:NondesignatedMember 2019-09-30 0001527469 us-gaap:CurrencySwapMember us-gaap:DesignatedAsHedgingInstrumentMember 2018-12-31 0001527469 ahl:InterestSensitiveContractsMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:NondesignatedMember 2019-09-30 0001527469 us-gaap:ForeignExchangeForwardMember us-gaap:NondesignatedMember 2019-09-30 0001527469 us-gaap:CurrencySwapMember us-gaap:NondesignatedMember 2018-12-31 0001527469 us-gaap:FutureMember us-gaap:NondesignatedMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:FundsWithheldatInterestMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:NondesignatedMember 2019-09-30 0001527469 us-gaap:ForeignExchangeForwardMember us-gaap:NondesignatedMember 2018-12-31 0001527469 ahl:InterestSensitiveContractsMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:NondesignatedMember 2018-12-31 0001527469 us-gaap:CreditDefaultSwapMember us-gaap:NondesignatedMember 2018-12-31 0001527469 us-gaap:CurrencySwapMember us-gaap:NondesignatedMember 2019-09-30 0001527469 us-gaap:FutureMember us-gaap:NondesignatedMember 2019-09-30 0001527469 us-gaap:StockOptionMember us-gaap:NondesignatedMember 2018-12-31 0001527469 us-gaap:NondesignatedMember 2019-09-30 0001527469 us-gaap:DesignatedAsHedgingInstrumentMember 2018-12-31 0001527469 ahl:FundsWithheldatInterestMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:NondesignatedMember 2018-12-31 0001527469 us-gaap:TotalReturnSwapMember us-gaap:NondesignatedMember 2018-12-31 0001527469 us-gaap:TotalReturnSwapMember us-gaap:NondesignatedMember 2019-09-30 0001527469 us-gaap:InterestRateSwapMember us-gaap:NondesignatedMember 2019-09-30 0001527469 us-gaap:ForeignExchangeForwardMember us-gaap:DesignatedAsHedgingInstrumentMember 2019-09-30 0001527469 us-gaap:NondesignatedMember 2018-12-31 0001527469 us-gaap:InterestRateSwapMember us-gaap:NondesignatedMember 2018-12-31 0001527469 us-gaap:DesignatedAsHedgingInstrumentMember 2019-09-30 0001527469 ahl:FundsWithheldatInterestMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:NondesignatedMember 2019-09-30 0001527469 us-gaap:ForeignExchangeForwardMember us-gaap:DesignatedAsHedgingInstrumentMember 2018-12-31 0001527469 ahl:InvestmentFundsMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:InterestSensitiveContractsMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember us-gaap:AvailableforsaleSecuritiesMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember srt:AffiliatedEntityMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ShortTermInvestmentsMember srt:AffiliatedEntityMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CorporateDebtSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember ahl:DebtSecuritiesTradingMember srt:AffiliatedEntityMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:LoansReceivableMember 2018-01-01 2018-09-30 0001527469 ahl:DebtSecuritiesTradingMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember ahl:DebtSecuritiesTradingMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember us-gaap:AvailableforsaleSecuritiesMember srt:AffiliatedEntityMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AvailableforsaleSecuritiesMember srt:AffiliatedEntityMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember srt:AffiliatedEntityMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember srt:AffiliatedEntityMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember ahl:DebtSecuritiesTradingMember srt:AffiliatedEntityMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:UniversalLifeMember ahl:InterestSensitiveContractsMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember ahl:DebtSecuritiesTradingMember 2017-12-31 0001527469 us-gaap:EquitySecuritiesMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember ahl:DebtSecuritiesTradingMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:USStatesAndPoliticalSubdivisionsMember ahl:DebtSecuritiesTradingMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ResidentialMortgageBackedSecuritiesMember ahl:DebtSecuritiesTradingMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:FundsWithheldatInterestMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:FundsWithheldatInterestMember srt:AffiliatedEntityMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ResidentialMortgageBackedSecuritiesMember ahl:DebtSecuritiesTradingMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember ahl:DebtSecuritiesTradingMember 2018-09-30 0001527469 ahl:DebtSecuritiesTradingMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember srt:AffiliatedEntityMember 2017-12-31 0001527469 ahl:InvestmentFundsMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AmerUsClosedBlockMember ahl:FuturePolicyBenefitsMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ReinsuranceRecoverableMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ReinsuranceRecoverableMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:UniversalLifeMember ahl:InterestSensitiveContractsMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember ahl:DebtSecuritiesTradingMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:DerivativeFinancialInstrumentsLiabilitiesMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember srt:AffiliatedEntityMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:FundsWithheldatInterestMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AmerUsClosedBlockMember ahl:FuturePolicyBenefitsMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember us-gaap:AvailableforsaleSecuritiesMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:UniversalLifeMember ahl:InterestSensitiveContractsMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember ahl:DebtSecuritiesTradingMember srt:AffiliatedEntityMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember us-gaap:AvailableforsaleSecuritiesMember 2018-09-30 0001527469 ahl:DebtSecuritiesTradingMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ShortTermInvestmentsMember srt:AffiliatedEntityMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ShortTermInvestmentsMember srt:AffiliatedEntityMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember ahl:DebtSecuritiesTradingMember srt:AffiliatedEntityMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember ahl:DebtSecuritiesTradingMember 2018-09-30 0001527469 ahl:InvestmentFundsMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CorporateDebtSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember srt:AffiliatedEntityMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:USStatesAndPoliticalSubdivisionsMember ahl:DebtSecuritiesTradingMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:FundsWithheldatInterestMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:DerivativeFinancialInstrumentsLiabilitiesMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:IndianapolisLifeInsuranceCompanyClosedBlockMember ahl:FuturePolicyBenefitsMember 2018-01-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ResidentialMortgageBackedSecuritiesMember ahl:DebtSecuritiesTradingMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:FundsWithheldatInterestMember srt:AffiliatedEntityMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:IndianapolisLifeInsuranceCompanyClosedBlockMember ahl:FuturePolicyBenefitsMember 2018-09-30 0001527469 ahl:InvestmentFundsMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember us-gaap:AvailableforsaleSecuritiesMember srt:AffiliatedEntityMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:LoansReceivableMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:InterestSensitiveContractsMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ReinsuranceRecoverableMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:DerivativeFinancialInstrumentsLiabilitiesMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:FundsWithheldatInterestMember srt:AffiliatedEntityMember 2018-09-30 0001527469 us-gaap:EquitySecuritiesMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:InterestSensitiveContractsMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember ahl:DebtSecuritiesTradingMember srt:AffiliatedEntityMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AmerUsClosedBlockMember ahl:FuturePolicyBenefitsMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:IndianapolisLifeInsuranceCompanyClosedBlockMember ahl:FuturePolicyBenefitsMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember us-gaap:AvailableforsaleSecuritiesMember srt:AffiliatedEntityMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember srt:AffiliatedEntityMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:USStatesAndPoliticalSubdivisionsMember ahl:DebtSecuritiesTradingMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:LoansReceivableMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CorporateDebtSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2017-12-31 0001527469 us-gaap:EquitySecuritiesMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2017-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember ahl:DebtSecuritiesTradingMember srt:AffiliatedEntityMember 2017-12-31 0001527469 srt:MinimumMember us-gaap:MeasurementInputWithdrawalRateMember 2018-12-31 0001527469 us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:FairValueInputsLevel3Member ahl:InterestSensitiveContractsMember 2018-12-31 0001527469 srt:MinimumMember us-gaap:MeasurementInputEntityCreditRiskMember 2018-12-31 0001527469 srt:MinimumMember us-gaap:MeasurementInputOptionVolatilityMember 2018-12-31 0001527469 srt:MaximumMember us-gaap:MeasurementInputOptionVolatilityMember 2018-12-31 0001527469 srt:MaximumMember us-gaap:MeasurementInputWithdrawalRateMember 2018-12-31 0001527469 srt:MaximumMember us-gaap:MeasurementInputEntityCreditRiskMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:FundsWithheldatInterestMember 2018-07-01 2018-09-30 0001527469 ahl:DebtSecuritiesTradingMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember us-gaap:AvailableforsaleSecuritiesMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:IndianapolisLifeInsuranceCompanyClosedBlockMember ahl:FuturePolicyBenefitsMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AmerUsClosedBlockMember ahl:FuturePolicyBenefitsMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember srt:AffiliatedEntityMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:FundsWithheldatInterestMember srt:AffiliatedEntityMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:UniversalLifeMember ahl:InterestSensitiveContractsMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:DerivativeFinancialInstrumentsLiabilitiesMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:FundsWithheldatInterestMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ResidentialMortgageBackedSecuritiesMember ahl:DebtSecuritiesTradingMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember ahl:DebtSecuritiesTradingMember srt:AffiliatedEntityMember 2018-07-01 2018-09-30 0001527469 ahl:InvestmentFundsMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember us-gaap:AvailableforsaleSecuritiesMember srt:AffiliatedEntityMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ShortTermInvestmentsMember srt:AffiliatedEntityMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember us-gaap:AvailableforsaleSecuritiesMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CorporateDebtSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-06-30 0001527469 ahl:DebtSecuritiesTradingMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember us-gaap:AvailableforsaleSecuritiesMember srt:AffiliatedEntityMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ReinsuranceRecoverableMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:InterestSensitiveContractsMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:UniversalLifeMember ahl:InterestSensitiveContractsMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember ahl:DebtSecuritiesTradingMember srt:AffiliatedEntityMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CorporateDebtSecuritiesMember ahl:DebtSecuritiesTradingMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ReinsuranceRecoverableMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember srt:AffiliatedEntityMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember ahl:DebtSecuritiesTradingMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CorporateDebtSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember ahl:DebtSecuritiesTradingMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CorporateDebtSecuritiesMember ahl:DebtSecuritiesTradingMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:LoansReceivableMember 2018-07-01 2018-09-30 0001527469 us-gaap:EquitySecuritiesMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:USStatesAndPoliticalSubdivisionsMember ahl:DebtSecuritiesTradingMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember ahl:DebtSecuritiesTradingMember srt:AffiliatedEntityMember 2018-07-01 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember ahl:DebtSecuritiesTradingMember srt:AffiliatedEntityMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:IndianapolisLifeInsuranceCompanyClosedBlockMember ahl:FuturePolicyBenefitsMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:InterestSensitiveContractsMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember ahl:DebtSecuritiesTradingMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember ahl:DebtSecuritiesTradingMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:DerivativeFinancialInstrumentsLiabilitiesMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ResidentialMortgageBackedSecuritiesMember ahl:DebtSecuritiesTradingMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:LoansReceivableMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AmerUsClosedBlockMember ahl:FuturePolicyBenefitsMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember srt:AffiliatedEntityMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:USStatesAndPoliticalSubdivisionsMember ahl:DebtSecuritiesTradingMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember 2018-06-30 0001527469 ahl:InvestmentFundsMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember srt:AffiliatedEntityMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CorporateDebtSecuritiesMember ahl:DebtSecuritiesTradingMember 2018-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ShortTermInvestmentsMember srt:AffiliatedEntityMember 2018-06-30 0001527469 us-gaap:EquitySecuritiesMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:FundsWithheldatInterestMember srt:AffiliatedEntityMember 2018-06-30 0001527469 ahl:InvestmentFundsMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-07-01 2018-09-30 0001527469 srt:MinimumMember us-gaap:MeasurementInputWithdrawalRateMember 2019-09-30 0001527469 srt:MaximumMember us-gaap:MeasurementInputEntityCreditRiskMember 2019-09-30 0001527469 us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:FairValueInputsLevel3Member ahl:InterestSensitiveContractsMember 2019-09-30 0001527469 srt:MinimumMember us-gaap:MeasurementInputOptionVolatilityMember 2019-09-30 0001527469 srt:MaximumMember us-gaap:MeasurementInputWithdrawalRateMember 2019-09-30 0001527469 srt:MinimumMember us-gaap:MeasurementInputEntityCreditRiskMember 2019-09-30 0001527469 srt:MaximumMember us-gaap:MeasurementInputOptionVolatilityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:UniversalLifeMember ahl:InterestSensitiveContractsMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ShortTermInvestmentsMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AmerUsClosedBlockMember ahl:FuturePolicyBenefitsMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember ahl:DebtSecuritiesTradingMember srt:AffiliatedEntityMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:LoansReceivableMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CorporateDebtSecuritiesMember ahl:DebtSecuritiesTradingMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:InterestSensitiveContractsMember 2019-07-01 2019-09-30 0001527469 ahl:InvestmentFundsMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CorporateDebtSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:FundsWithheldatInterestMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ResidentialMortgageBackedSecuritiesMember ahl:DebtSecuritiesTradingMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:DerivativeFinancialInstrumentsLiabilitiesMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CorporateDebtSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember ahl:DebtSecuritiesTradingMember srt:AffiliatedEntityMember 2019-09-30 0001527469 ahl:DebtSecuritiesTradingMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:LoansReceivableMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember us-gaap:AvailableforsaleSecuritiesMember srt:AffiliatedEntityMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember ahl:DebtSecuritiesTradingMember srt:AffiliatedEntityMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember ahl:DebtSecuritiesTradingMember srt:AffiliatedEntityMember 2019-06-30 0001527469 ahl:DebtSecuritiesTradingMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember srt:AffiliatedEntityMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember srt:AffiliatedEntityMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:UniversalLifeMember ahl:InterestSensitiveContractsMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CorporateDebtSecuritiesMember ahl:DebtSecuritiesTradingMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember srt:AffiliatedEntityMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:USStatesAndPoliticalSubdivisionsMember us-gaap:AvailableforsaleSecuritiesMember 2019-07-01 2019-09-30 0001527469 us-gaap:EquitySecuritiesMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember ahl:DebtSecuritiesTradingMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ReinsuranceRecoverableMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember srt:AffiliatedEntityMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember ahl:DebtSecuritiesTradingMember srt:AffiliatedEntityMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember us-gaap:AvailableforsaleSecuritiesMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:IndianapolisLifeInsuranceCompanyClosedBlockMember ahl:FuturePolicyBenefitsMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember srt:AffiliatedEntityMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember ahl:DebtSecuritiesTradingMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ShortTermInvestmentsMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:FundsWithheldatInterestMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember ahl:DebtSecuritiesTradingMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ReinsuranceRecoverableMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember us-gaap:AvailableforsaleSecuritiesMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember ahl:DebtSecuritiesTradingMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:FundsWithheldatInterestMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:USStatesAndPoliticalSubdivisionsMember us-gaap:AvailableforsaleSecuritiesMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AmerUsClosedBlockMember ahl:FuturePolicyBenefitsMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember us-gaap:AvailableforsaleSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember us-gaap:AvailableforsaleSecuritiesMember srt:AffiliatedEntityMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:FundsWithheldatInterestMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:DerivativeFinancialInstrumentsLiabilitiesMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:IndianapolisLifeInsuranceCompanyClosedBlockMember ahl:FuturePolicyBenefitsMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:FundsWithheldatInterestMember srt:AffiliatedEntityMember 2019-07-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:InterestSensitiveContractsMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:DerivativeFinancialInstrumentsLiabilitiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ReinsuranceRecoverableMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:LoansReceivableMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:IndianapolisLifeInsuranceCompanyClosedBlockMember ahl:FuturePolicyBenefitsMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:USStatesAndPoliticalSubdivisionsMember us-gaap:AvailableforsaleSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ResidentialMortgageBackedSecuritiesMember ahl:DebtSecuritiesTradingMember 2019-06-30 0001527469 ahl:InvestmentFundsMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-06-30 0001527469 us-gaap:EquitySecuritiesMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ResidentialMortgageBackedSecuritiesMember ahl:DebtSecuritiesTradingMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember ahl:DebtSecuritiesTradingMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember us-gaap:AvailableforsaleSecuritiesMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CorporateDebtSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember 2019-06-30 0001527469 us-gaap:EquitySecuritiesMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember ahl:DebtSecuritiesTradingMember 2019-09-30 0001527469 ahl:InvestmentFundsMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:FundsWithheldatInterestMember srt:AffiliatedEntityMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ShortTermInvestmentsMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AmerUsClosedBlockMember ahl:FuturePolicyBenefitsMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CorporateDebtSecuritiesMember ahl:DebtSecuritiesTradingMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:InterestSensitiveContractsMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember srt:AffiliatedEntityMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:UniversalLifeMember ahl:InterestSensitiveContractsMember 2019-06-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember ahl:DebtSecuritiesTradingMember 2019-06-30 0001527469 ahl:DebtSecuritiesTradingMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-12-31 0001527469 us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ResidentialMortgageBackedSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:CommercialMortgageBackedSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:CorporateDebtSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:USTreasuryAndGovernmentMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CollateralizedDebtObligationsMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:AssetBackedSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:AssetBackedSecuritiesMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CollateralizedDebtObligationsMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:AssetBackedSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:AssetBackedSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:UniversalLifeMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember 2018-12-31 0001527469 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ResidentialMortgageBackedSecuritiesMember 2018-12-31 0001527469 us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:USTreasuryAndGovernmentMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:USStatesAndPoliticalSubdivisionsMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CorporateDebtSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:AssetBackedSecuritiesMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:USTreasuryAndGovernmentMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CollateralizedDebtObligationsMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ResidentialMortgageBackedSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CorporateDebtSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CommercialMortgageBackedSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CommercialMortgageBackedSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:CollateralizedDebtObligationsMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:USStatesAndPoliticalSubdivisionsMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignGovernmentDebtSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:USStatesAndPoliticalSubdivisionsMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CollateralizedDebtObligationsMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:ResidentialMortgageBackedSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignGovernmentDebtSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:CollateralizedDebtObligationsMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AmerUsClosedBlockMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CollateralizedDebtObligationsMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:AssetBackedSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:UniversalLifeMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CommercialMortgageBackedSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CollateralizedDebtObligationsMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:IndianapolisLifeInsuranceCompanyClosedBlockMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CorporateDebtSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:IndianapolisLifeInsuranceCompanyClosedBlockMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:UniversalLifeMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:AssetBackedSecuritiesMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AmerUsClosedBlockMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AmerUsClosedBlockMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:AssetBackedSecuritiesMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:UniversalLifeMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignGovernmentDebtSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:USStatesAndPoliticalSubdivisionsMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:IndianapolisLifeInsuranceCompanyClosedBlockMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:USTreasuryAndGovernmentMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AmerUsClosedBlockMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignGovernmentDebtSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:IndianapolisLifeInsuranceCompanyClosedBlockMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:EstimateOfFairValueFairValueDisclosureMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:EstimateOfFairValueFairValueDisclosureMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CarryingReportedAmountFairValueDisclosureMember srt:AffiliatedEntityMember 2019-09-30 0001527469 us-gaap:FairValueInputsLevel3Member us-gaap:EstimateOfFairValueFairValueDisclosureMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:EstimateOfFairValueFairValueDisclosureMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CarryingReportedAmountFairValueDisclosureMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember us-gaap:EstimateOfFairValueFairValueDisclosureMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:EstimateOfFairValueFairValueDisclosureMember 2019-09-30 0001527469 us-gaap:CarryingReportedAmountFairValueDisclosureMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:EstimateOfFairValueFairValueDisclosureMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:EstimateOfFairValueFairValueDisclosureMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember us-gaap:EstimateOfFairValueFairValueDisclosureMember 2019-09-30 0001527469 us-gaap:FairValueInputsLevel2Member us-gaap:EstimateOfFairValueFairValueDisclosureMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember us-gaap:EstimateOfFairValueFairValueDisclosureMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 us-gaap:EstimateOfFairValueFairValueDisclosureMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 us-gaap:FairValueInputsLevel1Member us-gaap:EstimateOfFairValueFairValueDisclosureMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 us-gaap:LoansReceivableMember 2019-09-30 0001527469 us-gaap:LoansReceivableMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ShortTermInvestmentsMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AmerUsClosedBlockMember ahl:FuturePolicyBenefitsMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember ahl:DebtSecuritiesTradingMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:IndianapolisLifeInsuranceCompanyClosedBlockMember ahl:FuturePolicyBenefitsMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:LoansReceivableMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember ahl:DebtSecuritiesTradingMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember ahl:DebtSecuritiesTradingMember srt:AffiliatedEntityMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember srt:AffiliatedEntityMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:FundsWithheldatInterestMember srt:AffiliatedEntityMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember ahl:DebtSecuritiesTradingMember srt:AffiliatedEntityMember 2019-01-01 2019-09-30 0001527469 ahl:DebtSecuritiesTradingMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember srt:AffiliatedEntityMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember srt:AffiliatedEntityMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ResidentialMortgageBackedSecuritiesMember ahl:DebtSecuritiesTradingMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember us-gaap:AvailableforsaleSecuritiesMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:DerivativeFinancialInstrumentsLiabilitiesMember 2019-01-01 2019-09-30 0001527469 us-gaap:EquitySecuritiesMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:UniversalLifeMember ahl:InterestSensitiveContractsMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember ahl:DebtSecuritiesTradingMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:IndianapolisLifeInsuranceCompanyClosedBlockMember ahl:FuturePolicyBenefitsMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AmerUsClosedBlockMember ahl:FuturePolicyBenefitsMember 2018-12-31 0001527469 ahl:InvestmentFundsMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2019-01-01 2019-09-30 0001527469 us-gaap:EquitySecuritiesMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:FundsWithheldatInterestMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:InterestSensitiveContractsMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:USStatesAndPoliticalSubdivisionsMember us-gaap:AvailableforsaleSecuritiesMember 2018-12-31 0001527469 ahl:DebtSecuritiesTradingMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:USStatesAndPoliticalSubdivisionsMember us-gaap:AvailableforsaleSecuritiesMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember ahl:DebtSecuritiesTradingMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:InterestSensitiveContractsMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CorporateDebtSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EquitySecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CommercialMortgageBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:UniversalLifeMember ahl:InterestSensitiveContractsMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:FundsWithheldatInterestMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember ahl:FundsWithheldatInterestMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ReinsuranceRecoverableMember 2019-01-01 2019-09-30 0001527469 ahl:InvestmentFundsMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ResidentialMortgageBackedSecuritiesMember ahl:DebtSecuritiesTradingMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember ahl:DebtSecuritiesTradingMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CorporateDebtSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CollateralizedDebtObligationsMember us-gaap:AvailableforsaleSecuritiesMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:LoansReceivableMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ResidentialMortgageBackedSecuritiesMember us-gaap:AvailableforsaleSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:AssetBackedSecuritiesMember ahl:DebtSecuritiesTradingMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ReinsuranceRecoverableMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:ShortTermInvestmentsMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:DerivativeFinancialInstrumentsLiabilitiesMember 2018-12-31 0001527469 ahl:InvestmentFundsMember us-gaap:InvestmentIncomeMember 2018-07-01 2018-09-30 0001527469 us-gaap:LoansReceivableMember 2019-01-01 2019-09-30 0001527469 ahl:DebtSecuritiesTradingMember us-gaap:GainLossOnInvestmentsMember1 2019-01-01 2019-09-30 0001527469 us-gaap:InsuranceContractRightsAndObligationsFairValueOptionMember ahl:FuturePolicyBenefitsMember 2018-01-01 2018-09-30 0001527469 ahl:InvestmentFundsMember us-gaap:InvestmentIncomeMember 2019-01-01 2019-09-30 0001527469 ahl:InvestmentFundsMember us-gaap:InvestmentIncomeMember 2019-07-01 2019-09-30 0001527469 ahl:InvestmentFundsMember us-gaap:InvestmentIncomeMember 2018-01-01 2018-09-30 0001527469 us-gaap:LoansReceivableMember 2018-01-01 2018-09-30 0001527469 ahl:DebtSecuritiesTradingMember us-gaap:GainLossOnInvestmentsMember1 2018-07-01 2018-09-30 0001527469 us-gaap:InsuranceContractRightsAndObligationsFairValueOptionMember ahl:FuturePolicyBenefitsMember 2019-07-01 2019-09-30 0001527469 us-gaap:LoansReceivableMember 2018-07-01 2018-09-30 0001527469 ahl:DebtSecuritiesTradingMember us-gaap:GainLossOnInvestmentsMember1 2019-07-01 2019-09-30 0001527469 us-gaap:InsuranceContractRightsAndObligationsFairValueOptionMember ahl:FuturePolicyBenefitsMember 2018-07-01 2018-09-30 0001527469 ahl:DebtSecuritiesTradingMember us-gaap:GainLossOnInvestmentsMember1 2018-01-01 2018-09-30 0001527469 us-gaap:LoansReceivableMember 2019-07-01 2019-09-30 0001527469 us-gaap:InsuranceContractRightsAndObligationsFairValueOptionMember ahl:FuturePolicyBenefitsMember 2019-01-01 2019-09-30 0001527469 us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CommercialMortgageBackedSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:USStatesAndPoliticalSubdivisionsMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:USTreasuryAndGovernmentMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:IndianapolisLifeInsuranceCompanyClosedBlockMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:AssetBackedSecuritiesMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:USTreasuryAndGovernmentMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CommercialMortgageBackedSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CollateralizedDebtObligationsMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:IndianapolisLifeInsuranceCompanyClosedBlockMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:AssetBackedSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AmerUsClosedBlockMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ResidentialMortgageBackedSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:USStatesAndPoliticalSubdivisionsMember 2019-09-30 0001527469 us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CollateralizedDebtObligationsMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignGovernmentDebtSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:AssetBackedSecuritiesMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:USTreasuryAndGovernmentMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:UniversalLifeMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignGovernmentDebtSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:CorporateDebtSecuritiesMember srt:AffiliatedEntityMember 2019-09-30 0001527469 us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CollateralizedDebtObligationsMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:USTreasuryAndGovernmentMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CollateralizedDebtObligationsMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CorporateDebtSecuritiesMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:UniversalLifeMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:CollateralizedDebtObligationsMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignGovernmentDebtSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CorporateDebtSecuritiesMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CorporateDebtSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:AssetBackedSecuritiesMember 2019-09-30 0001527469 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CollateralizedDebtObligationsMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:USStatesAndPoliticalSubdivisionsMember 2019-09-30 0001527469 us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:CollateralizedDebtObligationsMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CollateralizedDebtObligationsMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CorporateDebtSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CommercialMortgageBackedSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CorporateDebtSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:AssetBackedSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:AssetBackedSecuritiesMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:CorporateDebtSecuritiesMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ResidentialMortgageBackedSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:USStatesAndPoliticalSubdivisionsMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:CorporateDebtSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:ResidentialMortgageBackedSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:UniversalLifeMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ForeignGovernmentDebtSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:AssetBackedSecuritiesMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AmerUsClosedBlockMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:IndianapolisLifeInsuranceCompanyClosedBlockMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:ResidentialMortgageBackedSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:UniversalLifeMember us-gaap:FairValueInputsLevel2Member us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember us-gaap:FairValueMeasurementsRecurringMember us-gaap:CommercialMortgageBackedSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:IndianapolisLifeInsuranceCompanyClosedBlockMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AmerUsClosedBlockMember us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember us-gaap:AssetBackedSecuritiesMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:AmerUsClosedBlockMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember 2019-09-30 0001527469 us-gaap:FairValueInputsLevel3Member us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EmbeddedDerivativeFinancialInstrumentsMember us-gaap:FairValueInputsLevel1Member us-gaap:FairValueMeasurementsRecurringMember srt:AffiliatedEntityMember 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember ahl:InvestmentFundsMember srt:AffiliatedEntityMember 2019-01-01 2019-09-30 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember 2018-12-31 0001527469 us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember us-gaap:EstimateOfFairValueFairValueDisclosureMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CarryingReportedAmountFairValueDisclosureMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:EstimateOfFairValueFairValueDisclosureMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:EstimateOfFairValueFairValueDisclosureMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel2Member us-gaap:EstimateOfFairValueFairValueDisclosureMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:EstimateOfFairValueFairValueDisclosureMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel3Member us-gaap:EstimateOfFairValueFairValueDisclosureMember srt:AffiliatedEntityMember 2018-12-31 0001527469 us-gaap:CarryingReportedAmountFairValueDisclosureMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-12-31 0001527469 us-gaap:FairValueInputsLevel2Member us-gaap:EstimateOfFairValueFairValueDisclosureMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember us-gaap:EstimateOfFairValueFairValueDisclosureMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:EstimateOfFairValueFairValueDisclosureMember srt:AffiliatedEntityMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:CarryingReportedAmountFairValueDisclosureMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueInputsLevel1Member us-gaap:EstimateOfFairValueFairValueDisclosureMember srt:AffiliatedEntityMember 2018-12-31 0001527469 us-gaap:EstimateOfFairValueFairValueDisclosureMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-12-31 0001527469 us-gaap:FairValueInputsLevel1Member us-gaap:EstimateOfFairValueFairValueDisclosureMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-12-31 0001527469 srt:ConsolidatedEntityExcludingVariableInterestEntitiesVIEMember us-gaap:FairValueMeasuredAtNetAssetValuePerShareMember us-gaap:EstimateOfFairValueFairValueDisclosureMember srt:AffiliatedEntityMember 2018-12-31 0001527469 us-gaap:FairValueInputsLevel3Member us-gaap:EstimateOfFairValueFairValueDisclosureMember srt:AffiliatedEntityMember us-gaap:VariableInterestEntityPrimaryBeneficiaryMember 2018-12-31 0001527469 srt:MaximumMember us-gaap:MeasurementInputDiscountRateMember 2018-12-31 0001527469 srt:MinimumMember us-gaap:MeasurementInputDiscountRateMember 2019-09-30 0001527469 srt:MaximumMember us-gaap:MeasurementInputDiscountRateMember 2019-09-30 0001527469 srt:MinimumMember us-gaap:MeasurementInputDiscountRateMember 2018-12-31 0001527469 srt:FederalHomeLoanBankOfDesMoinesMember us-gaap:ShortTermDebtMember us-gaap:FederalHomeLoanBankAdvancesMember us-gaap:SubsequentEventMember 2019-11-04 0001527469 srt:FederalHomeLoanBankOfDesMoinesMember us-gaap:ShortTermDebtMember us-gaap:FederalHomeLoanBankAdvancesMember us-gaap:SubsequentEventMember 2019-11-04 2019-11-04 0001527469 us-gaap:AccumulatedTranslationAdjustmentMember 2018-12-31 0001527469 us-gaap:AccumulatedTranslationAdjustmentMember 2019-09-30 0001527469 us-gaap:AccumulatedNetUnrealizedInvestmentGainLossMember 2019-09-30 0001527469 us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2019-09-30 0001527469 us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember 2019-09-30 0001527469 us-gaap:AccumulatedNetUnrealizedInvestmentGainLossMember 2018-12-31 0001527469 us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember 2018-12-31 0001527469 us-gaap:AccumulatedDefinedBenefitPlansAdjustmentMember 2018-12-31 0001527469 us-gaap:AccumulatedOtherThanTemporaryImpairmentMember 2018-12-31 0001527469 us-gaap:AccumulatedNetGainLossFromDesignatedOrQualifyingCashFlowHedgesMember 2019-09-30 0001527469 ahl:DeferredAcquisitionCostsDeferredSalesInducementsDeferredValueofBusinessAcquiredandFuturePolicyBenefitAdjustmentonAvailableforsaleSecuritiesAttributabletoParentMember 2019-09-30 0001527469 ahl:DeferredAcquisitionCostsDeferredSalesInducementsDeferredValueofBusinessAcquiredandFuturePolicyBenefitAdjustmentonAvailableforsaleSecuritiesAttributabletoParentMember 2018-12-31 0001527469 us-gaap:SeriesBPreferredStockMember 2019-09-30 2019-09-30 0001527469 ahl:RepurchaseAuthorization2018Member us-gaap:CommonClassAMember 2019-05-07 0001527469 us-gaap:SeriesBPreferredStockMember 2019-09-19 0001527469 us-gaap:SeriesAPreferredStockMember 2019-06-10 0001527469 ahl:RepurchaseAuthorization2018Member us-gaap:CommonClassAMember 2019-08-05 0001527469 ahl:RepurchaseAuthorization2018Member us-gaap:CommonClassAMember 2018-12-05 0001527469 ahl:RepurchaseAuthorization2018Member us-gaap:CommonClassAMember 2019-06-10 0001527469 us-gaap:SeriesAPreferredStockMember 2019-09-30 2019-09-30 0001527469 ahl:RepurchaseAuthorization2018Member us-gaap:CommonClassAMember us-gaap:SubsequentEventMember 2019-10-28 0001527469 us-gaap:AccumulatedNetGainLossFromCashFlowHedgesIncludingPortionAttributableToNoncontrollingInterestMember 2019-01-01 2019-09-30 0001527469 us-gaap:AccumulatedOtherthanTemporaryImpairmentIncludingPortionAttributableToNoncontrollingInterestMember 2018-07-01 2018-09-30 0001527469 ahl:AccumulatedNetInvestmentGainLossIncludingDeferredAcquisitionCostsDeferredSalesInducementsValueofBusinessAcquiredFuturePolicyBenefitsIncludingNoncontrollingInterestMember 2019-07-01 2019-09-30 0001527469 ahl:AccumulatedNetInvestmentGainLossIncludingDeferredAcquisitionCostsDeferredSalesInducementsValueofBusinessAcquiredFuturePolicyBenefitsIncludingNoncontrollingInterestMember 2019-01-01 2019-09-30 0001527469 us-gaap:AccumulatedForeignCurrencyAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember 2019-01-01 2019-09-30 0001527469 us-gaap:AccumulatedOtherthanTemporaryImpairmentIncludingPortionAttributableToNoncontrollingInterestMember 2019-07-01 2019-09-30 0001527469 us-gaap:AccumulatedNetGainLossFromCashFlowHedgesIncludingPortionAttributableToNoncontrollingInterestMember 2019-07-01 2019-09-30 0001527469 us-gaap:AccumulatedDefinedBenefitPlansAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember 2018-07-01 2018-09-30 0001527469 us-gaap:AccumulatedNetGainLossFromCashFlowHedgesIncludingPortionAttributableToNoncontrollingInterestMember 2018-07-01 2018-09-30 0001527469 us-gaap:AccumulatedOtherthanTemporaryImpairmentIncludingPortionAttributableToNoncontrollingInterestMember 2018-01-01 2018-09-30 0001527469 us-gaap:AccumulatedOtherthanTemporaryImpairmentIncludingPortionAttributableToNoncontrollingInterestMember 2019-01-01 2019-09-30 0001527469 us-gaap:AccumulatedDefinedBenefitPlansAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember 2019-01-01 2019-09-30 0001527469 ahl:AccumulatedNetInvestmentGainLossIncludingDeferredAcquisitionCostsDeferredSalesInducementsValueofBusinessAcquiredFuturePolicyBenefitsIncludingNoncontrollingInterestMember 2018-01-01 2018-09-30 0001527469 us-gaap:AccumulatedForeignCurrencyAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember 2018-01-01 2018-09-30 0001527469 ahl:DeferredAcquisitionCostsDeferredSalesInducementsDeferredValueofBusinessAcquiredandFuturePolicyBenefitAdjustmentIncludingPortionAttributabletoNoncontrollingInterestMember 2019-01-01 2019-09-30 0001527469 us-gaap:AccumulatedNetInvestmentGainLossIncludingPortionAttributableToNoncontrollingInterestMember 2018-01-01 2018-09-30 0001527469 us-gaap:AccountingStandardsUpdate201601Member us-gaap:AociIncludingPortionAttributableToNoncontrollingInterestMember 2019-01-01 0001527469 us-gaap:AccountingStandardsUpdate201601Member us-gaap:AociIncludingPortionAttributableToNoncontrollingInterestMember 2018-01-01 0001527469 ahl:DeferredAcquisitionCostsDeferredSalesInducementsDeferredValueofBusinessAcquiredandFuturePolicyBenefitAdjustmentIncludingPortionAttributabletoNoncontrollingInterestMember 2019-07-01 2019-09-30 0001527469 us-gaap:AccumulatedForeignCurrencyAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember 2018-07-01 2018-09-30 0001527469 ahl:DeferredAcquisitionCostsDeferredSalesInducementsDeferredValueofBusinessAcquiredandFuturePolicyBenefitAdjustmentIncludingPortionAttributabletoNoncontrollingInterestMember 2018-07-01 2018-09-30 0001527469 ahl:DeferredAcquisitionCostsDeferredSalesInducementsDeferredValueofBusinessAcquiredandFuturePolicyBenefitAdjustmentIncludingPortionAttributabletoNoncontrollingInterestMember 2018-01-01 2018-09-30 0001527469 us-gaap:AccumulatedNetInvestmentGainLossIncludingPortionAttributableToNoncontrollingInterestMember 2019-01-01 2019-09-30 0001527469 ahl:AccumulatedNetInvestmentGainLossIncludingDeferredAcquisitionCostsDeferredSalesInducementsValueofBusinessAcquiredFuturePolicyBenefitsIncludingNoncontrollingInterestMember 2018-07-01 2018-09-30 0001527469 us-gaap:AccumulatedNetGainLossFromCashFlowHedgesIncludingPortionAttributableToNoncontrollingInterestMember 2018-01-01 2018-09-30 0001527469 us-gaap:AccumulatedDefinedBenefitPlansAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember 2019-07-01 2019-09-30 0001527469 us-gaap:AccumulatedForeignCurrencyAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember 2019-07-01 2019-09-30 0001527469 us-gaap:AccountingStandardsUpdate201601Member us-gaap:AociIncludingPortionAttributableToNoncontrollingInterestMember 2018-07-01 0001527469 us-gaap:AccountingStandardsUpdate201601Member us-gaap:AociIncludingPortionAttributableToNoncontrollingInterestMember 2019-07-01 0001527469 us-gaap:AccumulatedNetInvestmentGainLossIncludingPortionAttributableToNoncontrollingInterestMember 2019-07-01 2019-09-30 0001527469 us-gaap:AccumulatedNetInvestmentGainLossIncludingPortionAttributableToNoncontrollingInterestMember 2018-07-01 2018-09-30 0001527469 us-gaap:AccumulatedDefinedBenefitPlansAdjustmentIncludingPortionAttributableToNoncontrollingInterestMember 2018-01-01 2018-09-30 0001527469 ahl:RepurchaseAuthorization2018Member us-gaap:CommonClassAMember us-gaap:SubsequentEventMember 2019-11-05 0001527469 ahl:RepurchaseAuthorization2018Member us-gaap:CommonClassAMember 2019-09-30 0001527469 ahl:RepurchaseAuthorization2018Member us-gaap:CommonClassAMember 2019-01-01 2019-09-30 0001527469 ahl:RepurchaseAuthorization2018Member us-gaap:CommonClassAMember 2018-10-01 2018-12-31 0001527469 ahl:RepurchaseAuthorization2018Member us-gaap:CommonClassAMember 2018-12-31 0001527469 ahl:RepurchaseAuthorization2018Member us-gaap:CommonClassAMember us-gaap:SubsequentEventMember 2019-10-01 2019-11-05 0001527469 ahl:ApolloandAffiliatesMember ahl:AssetsSubAdvisedMember srt:AffiliatedEntityMember 2018-12-31 0001527469 ahl:ApolloandAffiliatesMember us-gaap:CommercialMortgageBackedSecuritiesMember ahl:AssetsSubAdvisedMember srt:AffiliatedEntityMember 2018-12-31 0001527469 ahl:ApolloandAffiliatesMember us-gaap:AssetBackedSecuritiesMember ahl:AssetsSubAdvisedMember srt:AffiliatedEntityMember 2018-12-31 0001527469 ahl:ApolloandAffiliatesMember us-gaap:CollateralizedDebtObligationsMember ahl:AssetsSubAdvisedMember srt:AffiliatedEntityMember 2018-12-31 0001527469 ahl:ApolloandAffiliatesMember us-gaap:ForeignGovernmentDebtSecuritiesMember ahl:AssetsSubAdvisedMember srt:AffiliatedEntityMember 2018-12-31 0001527469 ahl:ApolloandAffiliatesMember us-gaap:CorporateDebtSecuritiesMember ahl:AssetsSubAdvisedMember srt:AffiliatedEntityMember 2018-12-31 0001527469 ahl:ApolloandAffiliatesMember ahl:SuballocatedassetsMember srt:AffiliatedEntityMember 2019-01-01 2019-09-30 0001527469 ahl:MidCapHoldingsMember srt:AffiliatedEntityMember 2018-12-31 0001527469 ahl:VenerableHoldingsInc.Member srt:AffiliatedEntityMember 2019-01-01 2019-09-30 0001527469 ahl:CoreSuballocationAssetsMember ahl:ApolloandAffiliatesMember ahl:SuballocatedassetsMember srt:AffiliatedEntityMember 2019-01-01 2019-09-30 0001527469 ahl:AtheneAssetManagementMember ahl:PortfolioManagementAgreementMember srt:AffiliatedEntityMember 2018-01-01 0001527469 ahl:ApolloOperatingGroupMember srt:AffiliatedEntityMember us-gaap:SubsequentEventMember 2019-10-27 0001527469 ahl:AmeriHomeMember ahl:PurchaseofResidentialMortgageLoansUnderAgreementMember srt:AffiliatedEntityMember 2018-01-01 2018-09-30 0001527469 ahl:AthoraHoldingLtd.Member ahl:FundingAgreementsMember srt:AffiliatedEntityMember 2018-12-31 0001527469 ahl:ManagementFeesAssociatedwithInvestmentFundsMember srt:AffiliatedEntityMember 2018-12-31 0001527469 ahl:ApolloOperatingGroupMember ahl:ExchangeofstockMember srt:AffiliatedEntityMember us-gaap:CommonClassAMember us-gaap:SubsequentEventMember 2019-10-27 0001527469 ahl:ApolloandAffiliatesMember ahl:SubAdvisoryFeesAssociatedwithInvestmentFundManagementMember srt:AffiliatedEntityMember 2019-09-30 0001527469 ahl:MidCapHoldingsMember srt:AffiliatedEntityMember 2018-12-31