cm:Concept: us-gaap:TranslationAdjustmentFunctionalToReportingCurrencyGainLossReclassifiedToEarningsNetOfTax
| Translation Adjustment Functional to Reporting Currency, Gain (Loss), Reclassified to Earnings, Net of Tax |
| us-gaap:TranslationAdjustmentFunctionalToReportingCurrencyGainLossReclassifiedToEarningsNetOfTax |
| Amount of reclassification from other comprehensive income (loss) to earnings, after tax, related to translation from the functional currency to reporting currency, as a result of the sale or complete or substantially complete liquidation of an investment in a foreign entity. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| For Period (duration) |
| Debit |
| false |
| us-gaap:TranslationAdjustmentFunctionalToReportingCurrencyGainLossReclassifiedToEarningsNetOfTax |