v3.26.3
Fair Value of Financial Instruments - Changes in Fair Value Associated with Level III Financial Instruments (Details) - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Financial instruments and other inventory positions sold, but not yet purchased | Derivative contracts        
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance $ 4,461 $ 4,370 $ 6,534 $ 991
Purchases 0 0 0 0
Sales 0 0 0 0
Settlements 581 (1,779) (6,032) (2,475)
Transfers in 0 0 0 0
Transfers out 0 0 0 0
Total realized and unrealized gains/(losses) 7,909 4,043 12,449 8,118
Ending balance 12,951 6,634 12,951 6,634
Unrealized gains/(losses) for assets/(liabilities) held at period end 12,926 5,268 12,765 6,634
Financial instruments and other inventory positions owned | Derivative contracts        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance 4,056 5,523 2,352 1,819
Purchases 0 0 0 0
Sales 0 0 0 0
Settlements 1,674 (2,060) (941) (2,910)
Transfers in 0 0 0 0
Transfers out 0 0 0 0
Total realized and unrealized gains/(losses) 18,799 41 23,118 4,595
Ending balance 24,529 3,504 24,529 3,504
Unrealized gains/(losses) for assets/(liabilities) held at period end 24,141 1,379 24,308 3,233
Investments        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance 195,756 185,202 217,966 176,970
Purchases 3,601 6,580 10,946 41,067
Sales (2) (248) (13,240) (248)
Settlements 0 0 0 0
Transfers in 0 697 0 697
Transfers out 0 (5,000) (7,349) (13,182)
Total realized and unrealized gains/(losses) 489 1,976 (8,479) (16,097)
Ending balance 199,844 189,207 199,844 189,207
Unrealized gains/(losses) for assets/(liabilities) held at period end $ 2,353 $ 1,971 $ (8,496) $ (9,531)