cm:Table: us-gaap:PropertySubjectToOrAvailableForOperatingLeaseByMajorPropertyClassTable
| Property Subject to or Available for Operating Lease, by Major Property Class [Table] |
| us-gaap:PropertySubjectToOrAvailableForOperatingLeaseByMajorPropertyClassTable |
| A listing by major property class of the amount of lessor property under a leasing agreement, and available for lease (not currently under lease), at cost, between the lessor and the lessee as of the balance sheet date. |
| cm:Table |
| Text/String (xbrli:stringItemType) |
| For Period (duration) |
| (no balance type) |
| true |
| us-gaap:PropertySubjectToOrAvailableForOperatingLeaseByMajorPropertyClassTable |