cm:Concept: us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsCompensatedAbsences
| Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Compensated Absences |
| us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsCompensatedAbsences |
| Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from compensated absences (includes, but not limited to, sick and personal days). |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Debit |
| false |
| us-gaap:DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsCompensatedAbsences |