Financial Instruments with Off-Balance Sheet Risk (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
Dec. 31, 2025 |
|
| Financial Instruments with Off-Balance Sheet Risk [Abstract] | |||||
| Margin loans extended | $ 437.4 | $ 437.4 | $ 378.9 | ||
| Receivables from customers | 88.6 | 88.6 | $ 73.5 | ||
| Unsettled customer transactions | |||||