| Standard label: | Proceeds from (Payments for) Securities Purchased under Agreements to Resell |
| Name: | us-gaap:ProceedsFromPaymentsForSecuritiesPurchasedUnderAgreementsToResell |
| Documentation: | The net cash flow from purchases followed by sales of securities under terms of reverse repurchase agreements. |
| Object type: | cm:Concept |
| Data type: | Monetary (xbrli:monetaryItemType) |
| Period type: | For Period (duration) |
| Balance type: | Debit |
| Abstract: | false |
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:ProceedsFromPaymentsForSecuritiesPurchasedUnderAgreementsToResell |
| Label | Role | Language |
| Proceeds from (Payments for) Securities Purchased under Agreements to Resell | http://www.xbrl.org/2003/role/label | en-US |
| Proceeds from (Payments for) Securities Purchased under Agreements to Resell, Total | http://www.xbrl.org/2003/role/totalLabel | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 230 10 45 8 | http://fasb.org/us-gaap/role/ref/legacyRef | 230 |
| FASB Accounting Standards Codification 230 10 45 9 | http://fasb.org/us-gaap/role/ref/legacyRef | 230 |
| Part Of Roll Up: |
| us-gaap:ProceedsFromPaymentsForFederalFundsSoldAndSecuritiesPurchasedUnderAgreementsToResellNet |