| Standard label: | Interest Income, Federal Funds Sold and Securities Purchased under Agreements to Resell |
| Name: | us-gaap:InterestIncomeFederalFundsSoldAndSecuritiesPurchasedUnderAgreementsToResell |
| Documentation: | The aggregate interest income earned from (1) the lending of excess federal funds to another commercial bank requiring such for its legal reserve requirements and (2) securities purchased under agreements to resell. |
| 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:InterestIncomeFederalFundsSoldAndSecuritiesPurchasedUnderAgreementsToResell |
| Label | Role | Language |
| Interest Income, Federal Funds Sold and Securities Purchased under Agreements to Resell | http://www.xbrl.org/2003/role/label | en-US |
| Interest Income, Federal Funds Sold and Securities Purchased under Agreements to Resell, Total | http://www.xbrl.org/2003/role/totalLabel | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 942 220 S99 1 (SX 210.9-04.4) | http://fasb.org/us-gaap/role/ref/legacyRef | 942 |
| Part Of Roll Up: |
| us-gaap:NetInvestmentIncome |