cm:Concept: us-gaap:BusinessCombinationContingentConsiderationAssetCurrent
| Business Combination, Contingent Consideration, Asset, Current |
| us-gaap:BusinessCombinationContingentConsiderationAssetCurrent |
| Amount of asset recognized arising from contingent consideration in a business combination, expected to be realized within one year or the normal operating cycle, if longer. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Debit |
| false |
| us-gaap:BusinessCombinationContingentConsiderationAssetCurrent |