cm:Concept: us-gaap:DiscussionOfMethodOfMeasuringFairValueOfForeignCurrencyDerivatives
| Discussion of Method of Measuring Fair Value of Foreign Currency Derivatives |
| us-gaap:DiscussionOfMethodOfMeasuringFairValueOfForeignCurrencyDerivatives |
| Discussion of the methods used by the entity to estimate the fair value of foreign currency derivatives. |
| cm:Concept |
| Text/String (xbrli:stringItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:DiscussionOfMethodOfMeasuringFairValueOfForeignCurrencyDerivatives |