| Assets | — | — |
| Cash and cash equivalents | 544.48a | 451.28a |
| Cash segregated under federal regulations | 47.11a | 45.12a |
| Investments, at fair value | 165.26a | 134.86a |
| Accounts receivable, net of allowance of $982 and $577 as of December 31, 2024 and 2023, respectively | 91.85a | 89.84a |
| Receivables from broker-dealers, clearing organizations and customers | 357.73a | 687.94a |
| Goodwill | 236.71a | 236.71a |
| Intangible assets, net of accumulated amortization | 98.08a | 119.11a |
| Furniture, equipment, leasehold improvements and capitalized software, net of accumulated depreciation and amortization | 107.3a | 102.67a |
| Operating lease right-of-use assets | 58.13a | 63.05a |
| Prepaid expenses and other assets | 82.58a | 84.5a |
| Total assets | 1,789.22a | 2,015.07a |
| Liabilities and stockholders’ equity | — | — |
| Liabilities | — | — |
| Accrued employee compensation | 68.05a | 60.12a |
| Payables to broker-dealers, clearing organizations and customers | 218.85a | 537.4a |
| Income and other tax liabilities | 3.68a | 7.89a |
| Accounts payable, accrued expenses and other liabilities | 37.32a | 37.01a |
| Operating lease liabilities | 72.65a | 79.68a |
| Total liabilities | 400.56a | 722.1a |
| Stockholders’ equity | — | — |
| Preferred stock | 0a | 0a |
| Series A preferred stock | 0a | 0a |
| Common stock voting | 0.12a | 0.12a |
| Common stock non-voting | 0a | 0a |
| Additional paid-in capital | 350.7a | 333.29a |
| Treasury stock - common stock voting, at cost | -333.37a | -260.3a |
| Retained earnings | 1,405.9a | 1,244.22a |
| Accumulated other comprehensive loss | -34.7a | -24.37a |
| Total stockholders’ equity | 1,388.66a | 1,292.96a |
| Total liabilities and stockholders’ equity | 1,789.22a | 2,015.07a |