cm:Concept: us-gaap:ObligationWithJointAndSeveralLiabilityArrangementAmountReceivable
| Obligation with Joint and Several Liability Arrangement, Amount Receivable |
| us-gaap:ObligationWithJointAndSeveralLiabilityArrangementAmountReceivable |
| Amount of receivable from other entities recognized in the balance sheet resulting from the joint and several liability arrangement. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Debit |
| false |
| us-gaap:ObligationWithJointAndSeveralLiabilityArrangementAmountReceivable |