cm:Concept: us-gaap:PropertyPlantAndEquipmentEstimatedUsefulLives
| Property, Plant and Equipment, Estimated Useful Lives |
| us-gaap:PropertyPlantAndEquipmentEstimatedUsefulLives |
| Describes the periods of time over which an entity anticipates to receive utility from its property, plant and equipment (that is, the periods of time over which an entity allocates the initial cost of its property, plant and equipment). |
| cm:Concept |
| Text/String (xbrli:stringItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:PropertyPlantAndEquipmentEstimatedUsefulLives |