cm:Concept: us-gaap:BusinessCombinationIntegrationRelatedCosts
| Business Combination, Integration Related Costs |
| us-gaap:BusinessCombinationIntegrationRelatedCosts |
| Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| For Period (duration) |
| Debit |
| false |
| us-gaap:BusinessCombinationIntegrationRelatedCosts |