cm:Concept: us-gaap:CashFlowsBetweenTransferorAndTransfereeBeneficialInterest
| Cash Flows Between Transferor and Transferee, Beneficial Interest |
| us-gaap:CashFlowsBetweenTransferorAndTransfereeBeneficialInterest |
| Cash flows between transferee and transferor in payment of the transferor's beneficial interest related to a securitization, asset-backed financing arrangement, or similar transfer in which the transferor has continuing involvement with the transferred financial assets underlying the transaction. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| For Period (duration) |
| Debit |
| false |
| us-gaap:CashFlowsBetweenTransferorAndTransfereeBeneficialInterest |