| Standard label: | Interest Expense Domestic Deposit Liabilities, Withdrawal Penalties |
| Name: | us-gaap:InterestExpenseDomesticDepositLiabilitiesWithdrawalPenalties |
| Documentation: | Early withdrawal penalties on domestic deposits which discourage customer withdrawal prior to maturity. |
| Object type: | cm:Concept |
| Data type: | Monetary (xbrli:monetaryItemType) |
| Period type: | For Period (duration) |
| Balance type: | Credit |
| Abstract: | false |
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:InterestExpenseDomesticDepositLiabilitiesWithdrawalPenalties |
| Label | Role | Language |
| Interest Expense Domestic Deposit Liabilities, Withdrawal Penalties | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 942 220 S99 1 (SX 210.9-04.6) | http://fasb.org/us-gaap/role/ref/legacyRef | 942 |