cm:Level3TextBlock: us-gaap:ScheduleOfDebtorTroubledDebtRestructuringSubsequentPeriodsTextBlock
| Schedule of Debtor Troubled Debt Restructuring, Subsequent Periods [Table Text Block] |
| us-gaap:ScheduleOfDebtorTroubledDebtRestructuringSubsequentPeriodsTextBlock |
| Tabular disclosure of troubled debt restructurings in the periods following the restructuring, including: (1) a description of the portion of the recorded [restructured] debt which is contingently payable based on the occurrence of future events or circumstances; (2) the dollar amount of the portion of the recorded [restructured] debt which is contingently payable based on the occurrence of future events or circumstances; and (3) a description of the circumstance, events, or conditions that would cause payments to occur or the creditor to forgive the contingent portion of recorded debt. |
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| Text Block (HTML) (nonnum:textBlockItemType) |
| For Period (duration) |
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| us-gaap:ScheduleOfDebtorTroubledDebtRestructuringSubsequentPeriodsTextBlock |
| TroubledDebtRestructuringDebtorSubsequentPeriods |