 | us-gaap:DebtSecuritiesUnrealizedGainLoss | summation-item | http://fasb.org/us-gaap/role/statement/StatementOfCashFlowsIndirect |
 | us-gaap:NetRealizedOrUnrealizedGainLossOnTradingSecuritiesAbstract | parent-child | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecuritiesTmp04 |
 | us-gaap:DebtSecuritiesTradingGainLoss | summation-item | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecuritiesTmp04 |
 | us-gaap:DebtSecuritiesUnrealizedGainLossExcludingOtherThanTemporaryImpairment | summation-item | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecuritiesCalcAlt1 |
 | us-gaap:TradingSecuritiesUnrealizedHoldingGainLossAbstract | parent-child | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecurities |
 | us-gaap:DebtSecuritiesUnrealizedGainLossAbstract | parent-child | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecurities |
 | us-gaap:DebtSecuritiesUnrealizedGainLossExcludingOtherThanTemporaryImpairmentAbstract | parent-child | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecurities |
 | us-gaap:DebtSecuritiesTradingGainLoss | summation-item | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecurities |
 | us-gaap:DebtSecuritiesUnrealizedGainLossExcludingOtherThanTemporaryImpairmentAbstract | domain-member | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecuritiesScheduleOfGainLossOnInvestmentsTable |
 | us-gaap:TradingSecuritiesUnrealizedHoldingGainLossAbstract | domain-member | http://fasb.org/us-gaap/role/disclosure/InvestmentsDebtAndEquitySecuritiesScheduleOfTradingSecuritiesAndOtherTradingAssetsTable |