 | us-gaap:BankingMember | domain-member | http://fasb.org/us-gaap/role/eedm/ExtensibleEnumerationLists |
 | us-gaap:BankingMember | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfIncome |
 | us-gaap:BankingMember | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfIncomeStatementTable |
 | us-gaap:OtherThanSecuritiesInvestmentMember | parent-child | http://fasb.org/us-gaap/role/disclosure/InvestmentHoldings |
 | us-gaap:OtherThanSecuritiesInvestmentMember | domain-member | http://fasb.org/us-gaap/role/disclosure/InvestmentHoldings |
 | us-gaap:OtherThanSecuritiesInvestmentMember | parent-child | http://fasb.org/us-gaap/role/disclosure/SummaryOfInvestmentHoldings |
 | us-gaap:OtherThanSecuritiesInvestmentMember | domain-member | http://fasb.org/us-gaap/role/disclosure/SummaryOfInvestmentHoldings |
 | us-gaap:OtherThanSecuritiesInvestmentMember | parent-child | http://fasb.org/us-gaap/role/disclosure/OtherThanSecuritiesInvestmentHoldings |
 | us-gaap:OtherThanSecuritiesInvestmentMember | domain-member | http://fasb.org/us-gaap/role/disclosure/OtherThanSecuritiesInvestmentHoldingsInvestmentHoldingsOtherThanSecuritiesTable |
 | us-gaap:OtherThanSecuritiesInvestmentMember | parent-child | http://fasb.org/us-gaap/role/disclosure/InvestmentsFederalTaxNote |
 | us-gaap:OtherThanSecuritiesInvestmentMember | domain-member | http://fasb.org/us-gaap/role/disclosure/InvestmentsFederalTaxNoteFederalIncomeTaxNoteTable |
 | us-gaap:FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain | parent-child | http://fasb.org/us-gaap/role/disclosure/FinancialInstrumentsFairValueDisclosures |
 | us-gaap:FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByLiabilityClassDomain | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialInstrumentsFairValueDisclosuresFairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationTable |
 | us-gaap:OtherThanSecuritiesInvestmentMember | parent-child | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInvestmentCompany |
 | us-gaap:OtherThanSecuritiesInvestmentMember | domain-member | http://fasb.org/us-gaap/role/disclosure/FinancialServicesInvestmentCompanyInvestmentHoldingsTable |