cm:Level3TextBlock: us-gaap:ReconciliationOfAssetsFromSegmentToConsolidatedTextBlock
| Reconciliation of Assets from Segment to Consolidated [Table Text Block] |
| us-gaap:ReconciliationOfAssetsFromSegmentToConsolidatedTextBlock |
| Tabular disclosure of all significant reconciling items in the reconciliation of total assets from reportable segments to the entity's consolidated assets. |
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| Text Block (HTML) (nonnum:textBlockItemType) |
| For Period (duration) |
| (no balance type) |
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| us-gaap:ReconciliationOfAssetsFromSegmentToConsolidatedTextBlock |
| ReconciliationOfAssetsfromSegmentToConsolidated |