 | us-gaap:SecuritiesInvestmentMember | parent-child | http://fasb.org/us-gaap/role/disclosure/InvestmentHoldings |
 | us-gaap:OtherThanSecuritiesInvestmentMember | parent-child | http://fasb.org/us-gaap/role/disclosure/InvestmentHoldings |
 | us-gaap:SecuritiesInvestmentMember | domain-member | http://fasb.org/us-gaap/role/disclosure/InvestmentHoldings |
 | us-gaap:OtherThanSecuritiesInvestmentMember | domain-member | http://fasb.org/us-gaap/role/disclosure/InvestmentHoldings |
 | us-gaap:EquitySecuritiesMember | parent-child | http://fasb.org/us-gaap/role/disclosure/InvestmentsSoldNotYetPurchased |
 | us-gaap:FixedIncomeInvestmentsMember | parent-child | http://fasb.org/us-gaap/role/disclosure/InvestmentsSoldNotYetPurchased |
 | us-gaap:EquitySecuritiesMember | domain-member | http://fasb.org/us-gaap/role/disclosure/InvestmentsSoldNotYetPurchasedInvestmentsSoldNotYetPurchasedTable |
 | us-gaap:FixedIncomeInvestmentsMember | domain-member | http://fasb.org/us-gaap/role/disclosure/InvestmentsSoldNotYetPurchasedInvestmentsSoldNotYetPurchasedTable |
 | us-gaap:SecuritiesInvestmentMember | parent-child | http://fasb.org/us-gaap/role/disclosure/SummaryOfInvestmentHoldings |
 | us-gaap:OtherThanSecuritiesInvestmentMember | parent-child | http://fasb.org/us-gaap/role/disclosure/SummaryOfInvestmentHoldings |
 | us-gaap:SecuritiesInvestmentMember | domain-member | http://fasb.org/us-gaap/role/disclosure/SummaryOfInvestmentHoldings |
 | us-gaap:OtherThanSecuritiesInvestmentMember | domain-member | http://fasb.org/us-gaap/role/disclosure/SummaryOfInvestmentHoldings |
 | us-gaap:SecuritiesInvestmentMember | parent-child | http://fasb.org/us-gaap/role/disclosure/OtherThanSecuritiesInvestmentHoldings |
 | us-gaap:OtherThanSecuritiesInvestmentMember | parent-child | http://fasb.org/us-gaap/role/disclosure/OtherThanSecuritiesInvestmentHoldings |
 | us-gaap:SecuritiesInvestmentMember | domain-member | http://fasb.org/us-gaap/role/disclosure/OtherThanSecuritiesInvestmentHoldingsInvestmentHoldingsOtherThanSecuritiesTable |
 | us-gaap:OtherThanSecuritiesInvestmentMember | domain-member | http://fasb.org/us-gaap/role/disclosure/OtherThanSecuritiesInvestmentHoldingsInvestmentHoldingsOtherThanSecuritiesTable |
 | us-gaap:SecuritiesInvestmentMember | parent-child | http://fasb.org/us-gaap/role/disclosure/InvestmentsFederalTaxNote |
 | us-gaap:OtherThanSecuritiesInvestmentMember | parent-child | http://fasb.org/us-gaap/role/disclosure/InvestmentsFederalTaxNote |
 | us-gaap:SecuritiesInvestmentMember | domain-member | http://fasb.org/us-gaap/role/disclosure/InvestmentsFederalTaxNoteFederalIncomeTaxNoteTable |
 | us-gaap:OtherThanSecuritiesInvestmentMember | domain-member | http://fasb.org/us-gaap/role/disclosure/InvestmentsFederalTaxNoteFederalIncomeTaxNoteTable |
 | us-gaap:CashAndCashEquivalentsMember | parent-child | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecurities |
 | us-gaap:DebtSecuritiesMember | parent-child | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecurities |
 | us-gaap:EquitySecuritiesMember | parent-child | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecurities |
 | srt:PartnershipInterestMember | parent-child | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecurities |
 | us-gaap:CashAndCashEquivalentsMember | domain-member | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecuritiesScheduleOfInvestmentIncomeReportedAmountsByCategoryTable |
 | us-gaap:DebtSecuritiesMember | domain-member | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecuritiesScheduleOfInvestmentIncomeReportedAmountsByCategoryTable |
 | us-gaap:EquitySecuritiesMember | domain-member | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecuritiesScheduleOfInvestmentIncomeReportedAmountsByCategoryTable |
 | srt:PartnershipInterestMember | domain-member | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecuritiesScheduleOfInvestmentIncomeReportedAmountsByCategoryTable |
 | us-gaap:PrivateEquityFundsMember | parent-child | http://fasb.org/us-gaap/role/disclosure/FinancialInstrumentsFairValueDisclosures |
 | us-gaap:HedgeFundsMember | parent-child | http://fasb.org/us-gaap/role/disclosure/FinancialInstrumentsFairValueDisclosures |
 | us-gaap:EquityFundsMember | parent-child | http://fasb.org/us-gaap/role/disclosure/FinancialInstrumentsFairValueDisclosures |
 | us-gaap:RealEstateFundsMember | parent-child | http://fasb.org/us-gaap/role/disclosure/FinancialInstrumentsFairValueDisclosures |
 | us-gaap:VentureCapitalFundsMember | parent-child | http://fasb.org/us-gaap/role/disclosure/FinancialInstrumentsFairValueDisclosures |
 | us-gaap:PrivateEquityFundsMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialInstrumentsFairValueDisclosuresFairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareTable |
 | us-gaap:HedgeFundsMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialInstrumentsFairValueDisclosuresFairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareTable |
 | us-gaap:EquityFundsMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialInstrumentsFairValueDisclosuresFairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareTable |
 | us-gaap:RealEstateFundsMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialInstrumentsFairValueDisclosuresFairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareTable |
 | us-gaap:VentureCapitalFundsMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialInstrumentsFairValueDisclosuresFairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareTable |
 | us-gaap:CashAndCashEquivalentsMember | parent-child | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsurance |
 | us-gaap:MutualFundMember | parent-child | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsurance |
 | us-gaap:DebtSecuritiesMember | parent-child | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsurance |
 | us-gaap:EquitySecuritiesMember | parent-child | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsurance |
 | us-gaap:FixedMaturitiesMember | parent-child | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsurance |
 | srt:PartnershipInterestMember | parent-child | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsurance |
 | us-gaap:PolicyLoansMember | parent-child | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsurance |
 | us-gaap:RealEstateInvestmentMember | parent-child | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsurance |
 | us-gaap:MortgagesMember | parent-child | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsurance |
 | us-gaap:ShortTermInvestmentsMember | parent-child | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsurance |
 | us-gaap:OtherLongTermInvestmentsMember | parent-child | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsurance |
 | us-gaap:CashAndCashEquivalentsMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentTable |
 | us-gaap:MutualFundMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentTable |
 | us-gaap:DebtSecuritiesMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentTable |
 | us-gaap:EquitySecuritiesMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentTable |
 | us-gaap:FixedMaturitiesMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentTable |
 | srt:PartnershipInterestMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentTable |
 | us-gaap:PolicyLoansMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentTable |
 | us-gaap:RealEstateInvestmentMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentTable |
 | us-gaap:MortgagesMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentTable |
 | us-gaap:ShortTermInvestmentsMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentTable |
 | us-gaap:OtherLongTermInvestmentsMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfFairValueOfSeparateAccountsByMajorCategoryOfInvestmentTable |
 | us-gaap:CashAndCashEquivalentsMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfInvestmentIncomeReportedAmountsByCategoryTable |
 | us-gaap:MutualFundMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfInvestmentIncomeReportedAmountsByCategoryTable |
 | us-gaap:DebtSecuritiesMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfInvestmentIncomeReportedAmountsByCategoryTable |
 | us-gaap:EquitySecuritiesMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfInvestmentIncomeReportedAmountsByCategoryTable |
 | us-gaap:FixedMaturitiesMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfInvestmentIncomeReportedAmountsByCategoryTable |
 | srt:PartnershipInterestMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfInvestmentIncomeReportedAmountsByCategoryTable |
 | us-gaap:PolicyLoansMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfInvestmentIncomeReportedAmountsByCategoryTable |
 | us-gaap:RealEstateInvestmentMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfInvestmentIncomeReportedAmountsByCategoryTable |
 | us-gaap:MortgagesMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfInvestmentIncomeReportedAmountsByCategoryTable |
 | us-gaap:ShortTermInvestmentsMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfInvestmentIncomeReportedAmountsByCategoryTable |
 | us-gaap:OtherLongTermInvestmentsMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInsuranceScheduleOfInvestmentIncomeReportedAmountsByCategoryTable |
 | us-gaap:FixedMaturitiesMember | parent-child | http://fasb.org/us-gaap/role/disclosure/SECScheduleArticle12-15SummaryOfInvestments-OtherThanInvestmentsInRelatedParties |
 | us-gaap:EquitySecuritiesInvestmentSummaryMember | parent-child | http://fasb.org/us-gaap/role/disclosure/SECScheduleArticle12-15SummaryOfInvestments-OtherThanInvestmentsInRelatedParties |
 | us-gaap:MortgagesMember | parent-child | http://fasb.org/us-gaap/role/disclosure/SECScheduleArticle12-15SummaryOfInvestments-OtherThanInvestmentsInRelatedParties |
 | us-gaap:RealEstateInvestmentMember | parent-child | http://fasb.org/us-gaap/role/disclosure/SECScheduleArticle12-15SummaryOfInvestments-OtherThanInvestmentsInRelatedParties |
 | us-gaap:RealEstateAcquiredInSatisfactionOfDebtMember | parent-child | http://fasb.org/us-gaap/role/disclosure/SECScheduleArticle12-15SummaryOfInvestments-OtherThanInvestmentsInRelatedParties |
 | us-gaap:PolicyLoansMember | parent-child | http://fasb.org/us-gaap/role/disclosure/SECScheduleArticle12-15SummaryOfInvestments-OtherThanInvestmentsInRelatedParties |
 | us-gaap:OtherLongTermInvestmentsMember | parent-child | http://fasb.org/us-gaap/role/disclosure/SECScheduleArticle12-15SummaryOfInvestments-OtherThanInvestmentsInRelatedParties |
 | us-gaap:ShortTermInvestmentsMember | parent-child | http://fasb.org/us-gaap/role/disclosure/SECScheduleArticle12-15SummaryOfInvestments-OtherThanInvestmentsInRelatedParties |
 | us-gaap:FixedMaturitiesMember | domain-member | http://fasb.org/us-gaap/role/disclosure/SECScheduleArticle12-15SummaryOfInvestments-OtherThanInvestmentsInRelatedPartiesSummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTable |
 | us-gaap:EquitySecuritiesInvestmentSummaryMember | domain-member | http://fasb.org/us-gaap/role/disclosure/SECScheduleArticle12-15SummaryOfInvestments-OtherThanInvestmentsInRelatedPartiesSummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTable |
 | us-gaap:MortgagesMember | domain-member | http://fasb.org/us-gaap/role/disclosure/SECScheduleArticle12-15SummaryOfInvestments-OtherThanInvestmentsInRelatedPartiesSummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTable |
 | us-gaap:RealEstateInvestmentMember | domain-member | http://fasb.org/us-gaap/role/disclosure/SECScheduleArticle12-15SummaryOfInvestments-OtherThanInvestmentsInRelatedPartiesSummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTable |
 | us-gaap:RealEstateAcquiredInSatisfactionOfDebtMember | domain-member | http://fasb.org/us-gaap/role/disclosure/SECScheduleArticle12-15SummaryOfInvestments-OtherThanInvestmentsInRelatedPartiesSummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTable |
 | us-gaap:PolicyLoansMember | domain-member | http://fasb.org/us-gaap/role/disclosure/SECScheduleArticle12-15SummaryOfInvestments-OtherThanInvestmentsInRelatedPartiesSummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTable |
 | us-gaap:OtherLongTermInvestmentsMember | domain-member | http://fasb.org/us-gaap/role/disclosure/SECScheduleArticle12-15SummaryOfInvestments-OtherThanInvestmentsInRelatedPartiesSummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTable |
 | us-gaap:ShortTermInvestmentsMember | domain-member | http://fasb.org/us-gaap/role/disclosure/SECScheduleArticle12-15SummaryOfInvestments-OtherThanInvestmentsInRelatedPartiesSummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesTable |
 | us-gaap:SecuritiesInvestmentMember | parent-child | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInvestmentCompany |
 | us-gaap:OtherThanSecuritiesInvestmentMember | parent-child | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInvestmentCompany |
 | us-gaap:SecuritiesInvestmentMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInvestmentCompanyInvestmentHoldingsTable |
 | us-gaap:OtherThanSecuritiesInvestmentMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInvestmentCompanyInvestmentHoldingsTable |