| Standard label: | Provision for Loan, Lease, and Other Losses |
| Name: | us-gaap:ProvisionForLoanLeaseAndOtherLosses |
| Documentation: | Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value. |
| 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:ProvisionForLoanLeaseAndOtherLosses |
| Label | Role | Language |
| Provision for Loan, Lease, and Other Losses | http://www.xbrl.org/2003/role/label | en-US |
| Provision for Loan, Lease, and Other Losses, Total | http://www.xbrl.org/2003/role/totalLabel | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 230 10 45 28 (a) | http://fasb.org/us-gaap/role/ref/legacyRef | 230 |
| FASB Accounting Standards Codification 310 10 50 11B (c)(2) | http://fasb.org/us-gaap/role/ref/legacyRef | 310 |
| FASB Accounting Standards Codification 942 220 S99 1 (SX 210.9-04.11) | http://fasb.org/us-gaap/role/ref/legacyRef | 942 |