cm:Level2TextBlock: us-gaap:GovernmentContractorsContractsInProgressPolicyPolicyTextBlock
| Government Contractors, Contracts in Progress, Policy [Policy Text Block] |
| us-gaap:GovernmentContractorsContractsInProgressPolicyPolicyTextBlock |
| Disclosure of accounting policy for contracts in progress, including policies with respect to accounting for indirect costs and methods of measuring extent of progress toward completion if the percentage-of-completion method is used. |
| cm:Level2TextBlock |
| Text Block (HTML) (nonnum:textBlockItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:GovernmentContractorsContractsInProgressPolicyPolicyTextBlock |