cm:Level3TextBlock: us-gaap:ScheduleOfErrorCorrectionsAndPriorPeriodAdjustmentsTextBlock
| Schedule of Error Corrections and Prior Period Adjustments [Table Text Block] |
| us-gaap:ScheduleOfErrorCorrectionsAndPriorPeriodAdjustmentsTextBlock |
| Tabular disclosure of prior period adjustments to previously issued financial statements including (1) the effect of the correction on each financial statement line item and any per-share amounts affected for each prior period presented (2) the cumulative effect of the change on retained earnings or other appropriate components of equity or net assets in the statement of financial position, as of the beginning of the earliest period presented, and (3) the effect of the prior period adjustments (both gross and net of applicable income tax) on the net income of each prior period presented in the entity's annual report for the year in which the adjustments are made. |
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| us-gaap:ScheduleOfErrorCorrectionsAndPriorPeriodAdjustmentsTextBlock |
| ErrorCorrectionsAndPriorPeriodAdjustments |