| Standard label: | Principal Investment Gain (Loss) |
| Name: | us-gaap:PrincipalInvestmentGainsLosses |
| Documentation: | Amount of realized and unrealized gain (loss), from the firm's direct investment activity, conducted separately from customer trading activities, and includes, but is not limited to, investments in private equity, alternative investment products, real estate, and exchanges and memberships. |
| Object type: | cm:Concept |
| Data type: | Monetary (xbrli:monetaryItemType) |
| Period type: | For Period (duration) |
| Balance type: | Credit |
| Abstract: | false |
| Workiva Wdesk Taxonomy Analyzer: | us-gaap:PrincipalInvestmentGainsLosses |
| Label | Role | Language |
| Principal Investment Gain (Loss) | http://www.xbrl.org/2003/role/label | en-US |
| Reference | Role | Topic |
| FASB Accounting Standards Codification 942 220 S99 1 (SX 210.9-04.13(g),(h)) | http://fasb.org/us-gaap/role/ref/legacyRef | 942 |
| FASB Accounting Standards Codification 944 220 S99 1 (SX 210.7-04.2,3) | http://fasb.org/us-gaap/role/ref/legacyRef | 944 |
| Part Of Roll Up: |
| us-gaap:PrincipalTransactionsRevenue |