cm:Concept: us-gaap:TerminationLoansDescription
| Termination Loans, Description |
| us-gaap:TerminationLoansDescription |
| General description of liabilities to third parties under a termination loan agreement, whether or not guaranteed by the government, including a cross reference to the related termination claim or claims recorded or disclosed at the latest balance sheet date. |
| cm:Concept |
| Text/String (xbrli:stringItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:TerminationLoansDescription |