| Name | HeldToMaturitySecuritiesAmortizedCostBeforeOtherThanTemporaryImpairment |
|---|---|
| Namespace | http://fasb.org/us-gaap/2020-01-31 |
| Prefix | us-gaap |
| Data type | xbrli:monetaryItemType |
| Period type | instant |
| Substitution Group | xbrli:item |
| Balance | debit |
| Nillable | True |
| Abstract | False |
| Text | Lang | Role | Container role |
|---|---|---|---|
| Amount, before other-than-temporary impairment (OTTI) accretion, of investment in debt securities measured at amortized cost (held-to-maturity). | en-US | http://www.xbrl.org/2003/role/documentation | http://www.xbrl.org/2003/role/link |
| Debt Securities, Held-to-maturity, Amortized Cost, before Other-than-temporary Impairment | en-US | http://www.xbrl.org/2003/role/label | http://www.xbrl.org/2003/role/link |