cm:Level3TextBlock: us-gaap:ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock
| Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] |
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| Tabular disclosure of securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) in the future that were not included in the computation of diluted EPS because to do so would increase EPS amounts or decrease loss per share amounts for the period presented, by antidilutive securities. |
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| AntidilutiveSecuritiesExcludedfromComputationOfEarningsPerShare |