cm:Concept: us-gaap:ConcentrationRiskMarketRisk
| Concentration Risk, Market Risk |
| us-gaap:ConcentrationRiskMarketRisk |
| Description of risks that arise due to the volume of transactions the entity executes within a particular (nongeographic) market. The description may address the risks inherent in the market, and, at a minimum, informs financial statement users of the general nature of the risk. |
| cm:Concept |
| Text/String (xbrli:stringItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:ConcentrationRiskMarketRisk |