cm:Concept: us-gaap:SecuritiesSoldUnderAgreementsToRepurchaseNotSubjectToMasterNettingArrangementDeduction
| Securities Sold under Agreements to Repurchase, Not Subject to Master Netting Arrangement Deduction |
| us-gaap:SecuritiesSoldUnderAgreementsToRepurchaseNotSubjectToMasterNettingArrangementDeduction |
| Amount of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price, not subject to a master netting arrangement, deducted from securities sold under agreements to repurchase. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Debit |
| false |
| us-gaap:SecuritiesSoldUnderAgreementsToRepurchaseNotSubjectToMasterNettingArrangementDeduction |