cm:Level3TextBlock: us-gaap:InvestmentsInAndAdvancesToAffiliatesTextBlock
| Investments in and Advances to Affiliates [Table Text Block] |
| us-gaap:InvestmentsInAndAdvancesToAffiliatesTextBlock |
| Tabular disclosure of investments in and advances to affiliates. Does not include the tabular disclosure of the disaggregation of investments in and advances to affiliates across legal entities. |
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| us-gaap:InvestmentsInAndAdvancesToAffiliatesTextBlock |