cm:Concept: us-gaap:ConcentrationRiskMaterial
| Concentration Risk, Material |
| us-gaap:ConcentrationRiskMaterial |
| Description of risks that arise due to the entity's reliance on a particular material used in its operations and the availability of that material. The description would generally be expected to be adequate to inform financial statement users as to the general nature of the risk. |
| cm:Concept |
| Text/String (xbrli:stringItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:ConcentrationRiskMaterial |