cm:Concept: us-gaap:ProceedsFromDivestitureOfInterestInJointVenture
| Proceeds from Divestiture of Interest in Joint Venture |
| us-gaap:ProceedsFromDivestitureOfInterestInJointVenture |
| The cash inflow from the sale of an investment interest in a joint venture that the reporting entity has not previously accounted for using consolidation or the equity method of accounting. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| For Period (duration) |
| Debit |
| false |
| us-gaap:ProceedsFromDivestitureOfInterestInJointVenture |