cm:Level3TextBlock: us-gaap:ScheduleOfCostsOfRetirementPlansTableTextBlock
| Schedule of Costs of Retirement Plans [Table Text Block] |
| us-gaap:ScheduleOfCostsOfRetirementPlansTableTextBlock |
| Tabular disclosure of the costs related to the various types of retirement plans including defined benefit pension plan cost, defined contribution plan cost, other postretirement benefit plan cost, and net periodic benefit cost. |
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| Text Block (HTML) (nonnum:textBlockItemType) |
| For Period (duration) |
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| us-gaap:ScheduleOfCostsOfRetirementPlansTableTextBlock |
| CostsOfRetirementPlans |