cm:Level3TextBlock: us-gaap:ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock
       
          
          | Schedule of Deferred Tax Assets and Liabilities [Table Text Block] | 
       
       
          
          | us-gaap:ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock | 
       
       
          
          | Tabular disclosure of the components of net deferred tax asset or liability recognized in an entity's statement of financial position, including the following: the total of all deferred tax liabilities, the total of all deferred tax assets, the total valuation allowance recognized for deferred tax assets. | 
       
       
          
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          | Text Block (HTML) (nonnum:textBlockItemType) | 
       
       
          
          | For Period (duration) | 
       
       
          
          | (no balance type) | 
       
       
          
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          | us-gaap:ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock | 
       
       
          
          | DeferredTaxAssetsAndLiabilities |