cm:Concept: us-gaap:PaymentsToAcquireRetainedInterestInSecuritizedReceivables
| Payments to Acquire Retained Interest in Securitized Receivables |
| us-gaap:PaymentsToAcquireRetainedInterestInSecuritizedReceivables |
| The cash outflow for the purchase of a retained interest in a receivable securitized via a structured process whereby interests in loans and other receivables are packaged, underwritten, and sold in the form of asset-backed securities. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| For Period (duration) |
| Credit |
| false |
| us-gaap:PaymentsToAcquireRetainedInterestInSecuritizedReceivables |