cm:Concept: us-gaap:LoansAndLeasesReceivableCollateralForSecuredBorrowings
| Loans and Leases Receivable, Collateral for Secured Borrowings |
| us-gaap:LoansAndLeasesReceivableCollateralForSecuredBorrowings |
| Reflects the aggregate value of loans, trade receivables, securities and financial instruments that serve as collateral for obligations arising from a transfer of financial assets recorded as a secured borrowing. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Debit |
| false |
| us-gaap:LoansAndLeasesReceivableCollateralForSecuredBorrowings |