cm:Concept: us-gaap:PledgedFinancialInstrumentsNotSeparatelyReportedOnStatementOfFinancialPositionNote
| Pledged Financial Instruments and Other Assets, Not Separately Reported on Statement of Financial Position, Description |
| us-gaap:PledgedFinancialInstrumentsNotSeparatelyReportedOnStatementOfFinancialPositionNote |
| Description of financial instruments which are owned but transferred to serve as collateral to fully or partially secure a debt obligation, repurchase agreement or other current or potential obligation, and, because the secured party does not have the right by contract or custom to sell or re-pledge the financial instruments, are not reclassified and separately reported in the statement of financial position. Also sets forth the carrying amount and classification of pledged financial instruments as of the date of the latest statement of financial position presented. May also include other pledged assets not separately reported such as real estate. |
| cm:Concept |
| Text/String (xbrli:stringItemType) |
| For Period (duration) |
| (no balance type) |
| false |
| us-gaap:PledgedFinancialInstrumentsNotSeparatelyReportedOnStatementOfFinancialPositionNote |