cm:Concept: us-gaap:SharesSubjectToMandatoryRedemptionSettlementTermsMaximumAmount
| Financial Instruments Subject to Mandatory Redemption, Settlement Terms, Maximum Amount |
| us-gaap:SharesSubjectToMandatoryRedemptionSettlementTermsMaximumAmount |
| The maximum amount that the issuer could be required to pay to redeem the instrument by physical settlement, if applicable. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Credit |
| false |
| us-gaap:SharesSubjectToMandatoryRedemptionSettlementTermsMaximumAmount |