cm:Concept: us-gaap:FinancingReceivableCreditQualityAdditionalInformation
| Financing Receivable, Credit Quality, Additional Information |
| us-gaap:FinancingReceivableCreditQualityAdditionalInformation |
| Includes any additional disclosures related to the credit quality of financing receivables. This may include a description of a credit quality indicator or a description of how the internal risk ratings used by a company relate to the likelihood of loss. |
| cm:Concept |
| Text/String (xbrli:stringItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:FinancingReceivableCreditQualityAdditionalInformation |