cm:Concept: us-gaap:BasisOfProvisionForRefundsUnderGovernmentContracts
| Basis of Provision for Refunds under Government Contracts |
| us-gaap:BasisOfProvisionForRefundsUnderGovernmentContracts |
| General description as to the uncertainties, their significance, and the basis used in determining the amount of a provision recorded for expected refunds paid during the renegotiation of government contracts. |
| cm:Concept |
| Text/String (xbrli:stringItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:BasisOfProvisionForRefundsUnderGovernmentContracts |