cm:Concept: us-gaap:SubordinatedLongTermDebt
| Subordinated Long-term Debt, Noncurrent |
| us-gaap:SubordinatedLongTermDebt |
| Carrying value as of the balance sheet date of collateralized/uncollateralized debt obligation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Subordinated debt places a lender in a lien position behind the primary lender of the company. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Credit |
| false |
| us-gaap:SubordinatedLongTermDebt |