cm:Level3TextBlock: us-gaap:ScheduleOfDerivativeInstrumentsInStatementOfFinancialPositionFairValueTextBlock
| Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] |
| us-gaap:ScheduleOfDerivativeInstrumentsInStatementOfFinancialPositionFairValueTextBlock |
| Tabular disclosure of the location and fair value amounts of derivative instruments (and nonderivative instruments that are designated and qualify as hedging instruments) reported in the statement of financial position. |
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| us-gaap:ScheduleOfDerivativeInstrumentsInStatementOfFinancialPositionFairValueTextBlock |
| DerivativeInstrumentsInStatementOfFinancialPositionFairValue |