cm:Concept: us-gaap:HedgingLiabilitiesCurrent
| Hedging Liabilities, Current |
| us-gaap:HedgingLiabilitiesCurrent |
| Carrying amount as of the balance sheet date of the liability arising from a financial instrument or a contract used to mitigate a specified risk (hedge), and which are expected to be converted into cash or otherwise disposed of within a year or the normal operating cycle, if longer. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Credit |
| false |
| us-gaap:HedgingLiabilitiesCurrent |