cm:Member: us-gaap:GuaranteeOfBusinessRevenueMember
| Guarantee of Business Revenue [Member] |
| us-gaap:GuaranteeOfBusinessRevenueMember |
| Contracts that contingently require the indemnifying party (guarantor) to make payments to the indemnified party (guaranteed party) the amount by which the revenue of a specified business (or a specific portion of a business or for a specified product) for a specified period of time is less than a specified amount. |
| cm:Member |
| [Member] (nonnum:domainItemType) |
| For Period (duration) |
| (no balance type) |
| true |
| us-gaap:GuaranteeOfBusinessRevenueMember |