cm:Concept: us-gaap:UnrecordedUnconditionalPurchaseObligationDueInNextRollingTwelveMonths
| Unrecorded Unconditional Purchase Obligation, Due in Next Rolling Twelve Months |
| us-gaap:UnrecordedUnconditionalPurchaseObligationDueInNextRollingTwelveMonths |
| Amount of the fixed and determinable portion of the unrecorded unconditional purchase obligation maturing in the next rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Credit |
| false |
| us-gaap:UnrecordedUnconditionalPurchaseObligationDueInNextRollingTwelveMonths |