cm:Concept: us-gaap:TroubledDebtRestructuringDebtorCurrentPeriodDescriptionOfChangesInTerms
| Troubled Debt Restructuring, Debtor, Current Period, Description of Changes in Terms |
| us-gaap:TroubledDebtRestructuringDebtorCurrentPeriodDescriptionOfChangesInTerms |
| For a debtor, a description of the changes in terms of an existing debt, the major features of settlement, or both. This could include transferring to the creditor receivables from third parties, granting of equity interest in the debtor to the creditor, or modifying terms of the debt. |
| cm:Concept |
| Text/String (xbrli:stringItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:TroubledDebtRestructuringDebtorCurrentPeriodDescriptionOfChangesInTerms |