cm:Level3TextBlock: us-gaap:ScheduleOfSaleOfStockBySubsidiaryOrEquityMethodInvesteeDisclosureTextBlock
| Schedule of Sale of Stock by Subsidiary or Equity Method Investee Disclosure [Table Text Block] |
| us-gaap:ScheduleOfSaleOfStockBySubsidiaryOrEquityMethodInvesteeDisclosureTextBlock |
| Tabular disclosure of sales of stock or previously unissued stock made by subsidiary or equity method investee to investors outside the consolidated group. This includes stock issued in a business combination in exchange for shares of an acquired entity. |
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| Text Block (HTML) (nonnum:textBlockItemType) |
| For Period (duration) |
| (no balance type) |
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| us-gaap:ScheduleOfSaleOfStockBySubsidiaryOrEquityMethodInvesteeDisclosureTextBlock |
| SubsidiaryOrEquityMethodInvestee |