v3.26.1
Fair Value of Financial Instruments - Changes in Fair Value Associated with Level III Financial Instruments (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 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 $ 5,246 $ 2,278 $ 6,534 $ 991
Purchases 0 0 0 0
Sales 0 0 0 0
Settlements (3,589) (1,553) (6,071) (1,385)
Transfers in 0 0 0 0
Transfers out 0 0 0 0
Total realized and unrealized gains/(losses) 2,804 3,645 3,998 4,764
Ending balance 4,461 4,370 4,461 4,370
Unrealized gains/(losses) for assets/(liabilities) held at period end 3,627 3,109 3,546 4,016
Financial instruments and other inventory positions owned | Derivative contracts        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance 4,488 4,356 2,352 1,819
Purchases 0 0 0 0
Sales 0 0 0 0
Settlements (1,086) (1,403) (1,780) (1,330)
Transfers in 0 0 0 0
Transfers out 0 0 0 0
Total realized and unrealized gains/(losses) 654 2,570 3,484 5,034
Ending balance 4,056 5,523 4,056 5,523
Unrealized gains/(losses) for assets/(liabilities) held at period end 2,504 2,125 3,984 4,532
Investments        
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]        
Beginning balance 212,376 166,264 217,966 176,970
Purchases 6,062 23,001 7,345 34,487
Sales (6,959) 0 (13,238) 0
Settlements 0 0 0 0
Transfers in 0 0 0 0
Transfers out (7,349) 0 (7,349) (8,182)
Total realized and unrealized gains/(losses) (8,374) (4,063) (8,968) (18,073)
Ending balance 195,756 185,202 195,756 185,202
Unrealized gains/(losses) for assets/(liabilities) held at period end $ (12,034) $ (4,063) $ (16,455) $ (18,073)