cm:Level3TextBlock: us-gaap:OtherThanSecuritiesInvestmentHoldingsScheduleOfInvestmentsTextBlock
       
          
          | Other than Securities Investment Holdings, Schedule of Investments [Table Text Block] | 
       
       
          
          | us-gaap:OtherThanSecuritiesInvestmentHoldingsScheduleOfInvestmentsTextBlock | 
       
       
          
          | Tabular disclosure of the information required in the supplementary schedule applicable to management investment companies summarizing unaffiliated investments that are not securities. | 
       
       
          
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          | For Period (duration) | 
       
       
          
          | (no balance type) | 
       
       
          
          | false | 
       
       
          
          | us-gaap:OtherThanSecuritiesInvestmentHoldingsScheduleOfInvestmentsTextBlock |