| Standard label: | Security Owned and Pledged as Collateral, Fair Value |
| Name: | us-gaap:SecurityOwnedAndPledgedAsCollateralFairValue |
| Documentation: | Fair value of financial instrument held by the entity for its own account (proprietary securities) for trading or investment purposes that are carried at fair value and pledged to counterparties as collateral for financing transactions. |
| Object type: | cm:Concept |
| Data type: | Monetary (xbrli:monetaryItemType) |
| Period type: | As Of (instant) |
| Balance type: | Debit |
| Abstract: | false |
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:SecurityOwnedAndPledgedAsCollateralFairValue |
| Label | Role | Language |
| Security Owned and Pledged as Collateral, Fair Value | http://www.xbrl.org/2003/role/label | en-US |
| Security Owned and Pledged as Collateral, Fair Value, Total | http://www.xbrl.org/2003/role/totalLabel | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 860 30 50 1A (b)(1)(i) | http://fasb.org/us-gaap/role/ref/legacyRef | 860 |
| FASB Accounting Standards Codification 860 30 45 1 | http://fasb.org/us-gaap/role/ref/legacyRef | 860 |