cm:Concept: us-gaap:AllowanceForDoubtfulAccountsPremiumsAndOtherReceivables
| Allowance for Doubtful Accounts, Premiums and Other Receivables |
| us-gaap:AllowanceForDoubtfulAccountsPremiumsAndOtherReceivables |
| The valuation allowance as of the balance sheet date to reduce the gross amount of receivables to estimated net realizable value, which would be presented in parentheses on the face of the balance sheet. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Credit |
| false |
| us-gaap:AllowanceForDoubtfulAccountsPremiumsAndOtherReceivables |