cm:Level3TextBlock: us-gaap:ScheduleOfCashFlowHedgesIncludedInAccumulatedOtherComprehensiveIncomeLossTableTextBlock
| Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income (Loss) [Table Text Block] |
| us-gaap:ScheduleOfCashFlowHedgesIncludedInAccumulatedOtherComprehensiveIncomeLossTableTextBlock |
| Tabular disclosure of gain (loss) on derivative and nonderivative instruments designated and qualifying as cash flow hedge recorded in accumulated other comprehensive income (AOCI) and reclassified into earnings. |
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| For Period (duration) |
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