cm:Concept: us-gaap:DescriptionOfPossibleEffectsOfNoncomplianceOrLessThanMinimumNetWorthCapitalRequirements
| Description of Possible Effects of Noncompliance or Less than Minimum Net Worth Capital Requirements |
| us-gaap:DescriptionOfPossibleEffectsOfNoncomplianceOrLessThanMinimumNetWorthCapitalRequirements |
| Disclosure of the possible material effects of not being in compliance with capital adequacy requirements as of the balance sheet date, including the impact on amounts and disclosures in the financial statements. |
| cm:Concept |
| Text/String (xbrli:stringItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:DescriptionOfPossibleEffectsOfNoncomplianceOrLessThanMinimumNetWorthCapitalRequirements |