cm:Concept: us-gaap:WorkersCompensationLiabilityCurrent
| Workers' Compensation Liability, Current |
| us-gaap:WorkersCompensationLiabilityCurrent |
| Carrying value as of the balance sheet date of obligations and payables pertaining to claims incurred of a workers compensation nature. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Credit |
| false |
| us-gaap:WorkersCompensationLiabilityCurrent |