cm:Concept: us-gaap:LoansAndLeasesReceivableGrossCarryingAmount
| Loans and Leases Receivable, Gross |
| us-gaap:LoansAndLeasesReceivableGrossCarryingAmount |
| Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Debit |
| false |
| us-gaap:LoansAndLeasesReceivableGrossCarryingAmount |