cm:Level3TextBlock: us-gaap:ScheduleOfBusinessAcquisitionsByAcquisitionContingentConsiderationTextBlock
| Schedule of Business Acquisitions by Acquisition, Contingent Consideration [Table Text Block] |
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| Tabular disclosure of contingent payment arrangements including the terms that will result in payment and the accounting treatment that will be followed if such contingencies occur, including the potential impact on earnings per share if contingencies are to be settled in common stock of the entity. The description also may include the period over which amounts are expected to be paid, and changes in the amount since the previous reporting period. This also includes contingent options and commitments. |
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| BusinessAcquisitionsByAcquisitionContingentConsideration |