cm:Concept: us-gaap:DescriptionOfLocationOfGainLossOnInterestRateCashFlowHedgeDerivativeInFinancialStatements
| Description of Location of Gain (Loss) on Interest Rate Cash Flow Hedge Derivative in Financial Statements |
| us-gaap:DescriptionOfLocationOfGainLossOnInterestRateCashFlowHedgeDerivativeInFinancialStatements |
| Description of where the net gain (loss) on interest rate derivatives designated as cash flow hedges are reported in the statement of income or other statement of financial performance. Includes description of amounts included in other comprehensive income. |
| cm:Concept |
| Text/String (xbrli:stringItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:DescriptionOfLocationOfGainLossOnInterestRateCashFlowHedgeDerivativeInFinancialStatements |