cm:Concept: us-gaap:RestructuringAndRelatedActivitiesDescription
| Restructuring and Related Activities, Description |
| us-gaap:RestructuringAndRelatedActivitiesDescription |
| Description of a specific restructuring plan and related activities including the facts and circumstances leading to the restructuring or decision to exit an activity, and the expected completion date. This concept and related items would be utilized for each plan if multiple exit plans have been implemented in the period. |
| cm:Concept |
| Text/String (xbrli:stringItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:RestructuringAndRelatedActivitiesDescription |