cm:Level3TextBlock: us-gaap:ScheduleOfDebtorTroubledDebtRestructuringCurrentPeriodTextBlock
| Schedule of Debtor Troubled Debt Restructuring, Current Period [Table Text Block] |
| us-gaap:ScheduleOfDebtorTroubledDebtRestructuringCurrentPeriodTextBlock |
| Tabular disclosure of troubled debt restructurings in the current period: (1) for each restructuring, the principal changes in terms, the major features of settlement, or both; (2) the aggregate gain (loss) on restructuring of payables; (3) the income tax effect on the gain or loss recognized on the restructuring of payables; (4) the gain (loss) recognized on the restructuring of payables, after the impact of income tax expense or benefit; and (5) the aggregate gain (loss) on transfer of assets recognized during the period, after the impact of income tax expense or benefit. |
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| Text Block (HTML) (nonnum:textBlockItemType) |
| For Period (duration) |
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| TroubledDebtRestructuringDebtorCurrentPeriod |