cm:Level3TextBlock: us-gaap:ScheduleOfFairValueOffBalanceSheetRisksTextBlock
| Schedule of Fair Value, Off-balance Sheet Risks [Table Text Block] |
| us-gaap:ScheduleOfFairValueOffBalanceSheetRisksTextBlock |
| Tabular disclosure of the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined) which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition. |
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| Text Block (HTML) (nonnum:textBlockItemType) |
| For Period (duration) |
| (no balance type) |
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| us-gaap:ScheduleOfFairValueOffBalanceSheetRisksTextBlock |