cm:Concept: us-gaap:LongTermDebtPercentageBearingVariableInterestRate
| Long-term Debt, Percentage Bearing Variable Interest, Percentage Rate |
| us-gaap:LongTermDebtPercentageBearingVariableInterestRate |
| The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time. |
| cm:Concept |
| Percent (num:percentItemType) |
| As Of (instant) |
| (no balance type) |
| false |
| us-gaap:LongTermDebtPercentageBearingVariableInterestRate |