 | srt:FinancingReceivableBeforeAllowanceForCreditLossAverageYield | parent-child | http://fasb.org/srt/role/disclosure/FinancialServicesBankingAndThrift |
 | srt:TaxableInvestmentSecuritiesAverageYield | parent-child | http://fasb.org/srt/role/disclosure/FinancialServicesBankingAndThrift |
 | srt:NontaxableInvestmentSecuritiesAverageYield | parent-child | http://fasb.org/srt/role/disclosure/FinancialServicesBankingAndThrift |
 | srt:InterestBearingDepositsInBanksAverageYield | parent-child | http://fasb.org/srt/role/disclosure/FinancialServicesBankingAndThrift |
 | srt:FederalFundsSoldAverageYield | parent-child | http://fasb.org/srt/role/disclosure/FinancialServicesBankingAndThrift |
 | srt:SecuritiesPurchasedUnderAgreementsToResellAverageYield | parent-child | http://fasb.org/srt/role/disclosure/FinancialServicesBankingAndThrift |
 | srt:ShortTermInvestmentsOtherAverageYield | parent-child | http://fasb.org/srt/role/disclosure/FinancialServicesBankingAndThrift |
 | srt:InterestEarningAssetsAverageYield | parent-child | http://fasb.org/srt/role/disclosure/FinancialServicesBankingAndThrift |
 | srt:FinancingReceivableBeforeAllowanceForCreditLossAverageYield | domain-member | http://fasb.org/srt/role/disclosure/FinancialServicesBankingAndThriftDistributionOfAssetsLiabilitiesAndStockholdersEquityTable |
 | srt:TaxableInvestmentSecuritiesAverageYield | domain-member | http://fasb.org/srt/role/disclosure/FinancialServicesBankingAndThriftDistributionOfAssetsLiabilitiesAndStockholdersEquityTable |
 | srt:NontaxableInvestmentSecuritiesAverageYield | domain-member | http://fasb.org/srt/role/disclosure/FinancialServicesBankingAndThriftDistributionOfAssetsLiabilitiesAndStockholdersEquityTable |
 | srt:InterestBearingDepositsInBanksAverageYield | domain-member | http://fasb.org/srt/role/disclosure/FinancialServicesBankingAndThriftDistributionOfAssetsLiabilitiesAndStockholdersEquityTable |
 | srt:FederalFundsSoldAverageYield | domain-member | http://fasb.org/srt/role/disclosure/FinancialServicesBankingAndThriftDistributionOfAssetsLiabilitiesAndStockholdersEquityTable |
 | srt:SecuritiesPurchasedUnderAgreementsToResellAverageYield | domain-member | http://fasb.org/srt/role/disclosure/FinancialServicesBankingAndThriftDistributionOfAssetsLiabilitiesAndStockholdersEquityTable |
 | srt:ShortTermInvestmentsOtherAverageYield | domain-member | http://fasb.org/srt/role/disclosure/FinancialServicesBankingAndThriftDistributionOfAssetsLiabilitiesAndStockholdersEquityTable |
 | srt:InterestEarningAssetsAverageYield | domain-member | http://fasb.org/srt/role/disclosure/FinancialServicesBankingAndThriftDistributionOfAssetsLiabilitiesAndStockholdersEquityTable |