cm:Concept: us-gaap:AccountsReceivableUnapprovedContractClaims
| Accounts Receivable, Unapproved Contract Claims |
| us-gaap:AccountsReceivableUnapprovedContractClaims |
| The total amount of accounts receivable from customers under long-term contracts or programs associated with unapproved change orders or other similar items subject to uncertainty concerning their determination or ultimate realization. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Debit |
| false |
| us-gaap:AccountsReceivableUnapprovedContractClaims |