cm:Level3TextBlock: us-gaap:ScheduleOfCarryingValuesAndEstimatedFairValuesOfDebtInstrumentsTableTextBlock
| Schedule of Carrying Values and Estimated Fair Values of Debt Instruments [Table Text Block] |
| us-gaap:ScheduleOfCarryingValuesAndEstimatedFairValuesOfDebtInstrumentsTableTextBlock |
| Tabular disclosure of information pertaining to carrying amount and estimated fair value of short-term and long-term debt instruments or arrangements, including but not limited to, identification of terms, features, and collateral requirements. |
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| Text Block (HTML) (nonnum:textBlockItemType) |
| For Period (duration) |
| (no balance type) |
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| us-gaap:ScheduleOfCarryingValuesAndEstimatedFairValuesOfDebtInstrumentsTableTextBlock |