cm:Concept: us-gaap:DeferredIncomeTaxesAndOtherAssetsNoncurrent
| Deferred Income Taxes and Other Assets, Noncurrent |
| us-gaap:DeferredIncomeTaxesAndOtherAssetsNoncurrent |
| Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and other assets expected to be realized or consumed after one year or normal operating cycle, if longer. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Debit |
| false |
| us-gaap:DeferredIncomeTaxesAndOtherAssetsNoncurrent |