Derivatives - Summary of Gains and (Losses) on Derivative Contracts (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Principal transactions	Principal transactions
Gain (loss), net on derivative contract	$ 7,874	$ 6,447
Futures
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss), net on derivative contract	4,577	3,806
Interest rate swaps
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss), net on derivative contract	2,382	2,096
FX swaps
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss), net on derivative contract	821	498
FX/commodities options
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (loss), net on derivative contract	$ 94	$ 47

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4A

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