 | us-gaap:DebtSecuritiesHeldToMaturityExcludingAccruedInterestBeforeAllowanceForCreditLossNoncurrent | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassified |
 | us-gaap:DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterestNoncurrent | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassified |
 | us-gaap:DebtSecuritiesHeldToMaturityExcludingAccruedInterestAfterAllowanceForCreditLossNoncurrent | parent-child | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassified |
 | us-gaap:DebtSecuritiesHeldToMaturityExcludingAccruedInterestBeforeAllowanceForCreditLossNoncurrent | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassifiedStatementTable |
 | us-gaap:DebtSecuritiesHeldToMaturityAllowanceForCreditLossExcludingAccruedInterestNoncurrent | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassifiedStatementTable |
 | us-gaap:DebtSecuritiesHeldToMaturityExcludingAccruedInterestAfterAllowanceForCreditLossNoncurrent | domain-member | http://fasb.org/us-gaap/role/statement/StatementOfFinancialPositionClassifiedStatementTable |