cm:Level3TextBlock: us-gaap:InvestmentHoldingsOtherThanSecuritiesTextBlock
| Investment Holdings, Other than Securities [Table Text Block] |
| us-gaap:InvestmentHoldingsOtherThanSecuritiesTextBlock |
| Tabular disclosure of the investment holdings which are represented by other than securities (for example, commodities). The investment holdings, other than securities investments table lists the long positions of non-security investments held by entity. |
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| Text Block (HTML) (nonnum:textBlockItemType) |
| For Period (duration) |
| (no balance type) |
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| us-gaap:InvestmentHoldingsOtherThanSecuritiesTextBlock |