cm:Concept: us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivableLeasePaymentsToBeReceivedRollingYearThree
| Sales-type and Direct Financing Leases, Lease Receivable, Lease Payments to be Received, Rolling Year Three |
| us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivableLeasePaymentsToBeReceivedRollingYearThree |
| Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in third rolling twelve months following latest statement of financial position date. For interim and annual periods when interim periods are reported on rolling approach, from latest statement of financial position date. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Debit |
| false |
| us-gaap:SalesTypeAndDirectFinancingLeasesLeaseReceivableLeasePaymentsToBeReceivedRollingYearThree |