cm:Level3TextBlock: us-gaap:EquitySecuritiesWithoutReadilyDeterminableFairValueTableTextBlock
| Equity Securities without Readily Determinable Fair Value [Table Text Block] |
| us-gaap:EquitySecuritiesWithoutReadilyDeterminableFairValueTableTextBlock |
| Tabular disclosure of investment in equity security without readily determinable fair value. |
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| Text Block (HTML) (nonnum:textBlockItemType) |
| For Period (duration) |
| (no balance type) |
| false |
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