cm:Concept: us-gaap:DiscussionOfForeignCurrencyDerivativeRiskManagementPolicy
| Discussion of Foreign Currency Derivative Risk Management Policy |
| us-gaap:DiscussionOfForeignCurrencyDerivativeRiskManagementPolicy |
| Description of the entity's risk management policy for foreign currency exchange rate derivatives. Includes a description of the items or transactions for which risks are hedged, such as foreign currency exchange risk on foreign currency denominated sales. |
| cm:Concept |
| Text/String (xbrli:stringItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:DiscussionOfForeignCurrencyDerivativeRiskManagementPolicy |