cm:Level3TextBlock: us-gaap:ScheduleOfBusinessAcquisitionsByAcquisitionEquityInterestIssuedOrIssuableTextBlock
| Schedule of Business Acquisitions by Acquisition, Equity Interest Issued or Issuable [Table Text Block] |
| us-gaap:ScheduleOfBusinessAcquisitionsByAcquisitionEquityInterestIssuedOrIssuableTextBlock |
| Tabular disclosure of the equity interest issued or issuable in a business acquisition (or series of individually immaterial business acquisitions) planned, initiated, or completed during the period. |
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| Text Block (HTML) (nonnum:textBlockItemType) |
| For Period (duration) |
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| us-gaap:ScheduleOfBusinessAcquisitionsByAcquisitionEquityInterestIssuedOrIssuableTextBlock |
| BusinessAcquisitionsByAcquisitionEquityInterestIssuedOrIssuable |