cm:Level3TextBlock: us-gaap:ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock
| Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block] |
| us-gaap:ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock |
| Tabular disclosure of the reconciliation of profit (loss) from reportable segments to the consolidated income (loss) before income tax expense (benefit) and discontinued operations. Includes, but is not limited to, reconciliation after income tax if income tax is allocated to the reportable segment. |
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| us-gaap:ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock |
| ReconciliationOfOperatingProfitLossfromSegmentsToConsolidated |