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Receivables from and Payables to Broker-dealers, Clearing Organizations and Customers - Schedule of Receivables from and Payables to Broker-dealers, Clearing Organizations and Customers (Detail) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
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Receivables from broker-dealers, clearing organizations and customers: |  |
Securities failed-to-deliver - broker-dealers and clearing organizations | $ 184,441 | $ 109,307
Securities failed-to-deliver - customers | 297,606 | 136,424
Cash deposits with clearing organizations and broker-dealers | 119,942 | 107,652
Other | 4,678 | 4,345
Total | 606,667 | 357,728
Payables to broker-dealers, clearing organizations and customers: |  |
Securities failed-to-receive - broker-dealers and clearing organizations | 254,622 | 158,694
Securities failed-to-receive - customers | 101,514 | 51,916
Other | 9,692 | 8,235
Total | $ 365,828 | $ 218,845

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- Definition Amount payable to other broker-dealer and clearing organization, including, but not limited to, security failed-to-receive, deposit received for security loaned, open transaction, and floor-brokerage payable. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name Rule 15c3-1 -Number 240 -Section 15c3-1 -Publisher SEC Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 940 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481833/940-20-45-3 + Details
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- Definition Amount receivable from broker-dealers and clearing organizations, including, but not limited to, securities failed-to-deliver, certain deposits for securities borrowed, open transactions, good faith and margin deposits, commissions and floor brokerage receivables. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 940 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481833/940-20-45-3 + Details
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