cm:Level2TextBlock: us-gaap:RevenueRecognitionServicesRoyaltyFees
| Revenue Recognition, Services, Royalty Fees [Policy Text Block] |
| us-gaap:RevenueRecognitionServicesRoyaltyFees |
| Disclosure of accounting policy for revenue recognition for royalty fees, which is consideration or a share of the proceeds paid by another party to the owner of a right (that is, the entity) for its use. |
| cm:Level2TextBlock |
| Text Block (HTML) (nonnum:textBlockItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:RevenueRecognitionServicesRoyaltyFees |