cm:Level3TextBlock: us-gaap:FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareTableTextBlock
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share [Table Text Block] |
us-gaap:FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareTableTextBlock |
Tabular disclosure of investments in certain entities that calculate net asset value per share or equivalent measured at fair value on a recurring or nonrecurring basis. |
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us-gaap:FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareTableTextBlock |