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Compensation and Benefits - Additional information (Details) - USD ($) $ in Thousands | 9 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2022 | Dec. 31, 2024
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Number of shares available for grant (in shares) | 5,509,877 |  |  |
Shares paid for tax withholding for share based compensation (in shares) | 208,156 |  |  |
Share-Based Payment Arrangement, Decrease for Tax Withholding Obligation | $ 8,964 | $ 6,831 |  |
Potential Class A Shares associated with 2022 PSU grant performance criteria | 143,910 |  |  |
PSU outstanding subject only to qualified retirement (in shares) | 71,955 |  |  |
Maximum |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Share-Based Compensation Arrangement By Share-Based Payment Award, Award Requisite Service Period, Retirement Acceleration | 18 months |  |  |
Minimum |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Share-Based Compensation Arrangement By Share-Based Payment Award, Award Requisite Service Period, Retirement Acceleration | 12 months |  |  |
Class A Common Stock |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Shares delivered | 71,955 |  |  |
Shares paid for tax withholding for share based compensation (in shares) | 187,311 |  |  |
Restricted Stock |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Requisite service period (in years) | 5 years |  |  |
Granted - Number of awards (in shares) | 436,213 |  |  |
Unvested - Number of awards (in shares) | 5,170,266 |  |  | 5,276,480
Unrecognized compensation expense | $ 50,400 |  |  |
Recognition period (in years) | 2 years 7 months 6 days |  |  |
Shares paid for tax withholding for share based compensation (in shares) | 187,311 |  |  |
Performance Shares |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Requisite service period (in years) | 3 years |  |  |
Granted - Number of awards (in shares) | 0 |  | 95,940 |
Unvested - Number of awards (in shares) | 152,207 |  |  | 176,192
Unrecognized compensation expense | $ 500 |  |  |
Recognition period (in years) | 1 year 1 month 6 days |  |  |
Adjustment for performance results achieved (in shares) | 47,970 |  |  |
Restricted Stock Awards |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Granted - Number of awards (in shares) | 429,511 |  |  |
Restricted Stock Units RSUs |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Granted - Number of awards (in shares) | 6,702 |  |  |
Long-Term Cash Awards | Deferred Bonus |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Requisite service period (in years) | 5 years |  |  |
Awards granted, amount | $ 46,800 |  |  |
Deferred Bonus |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Unrecognized compensation expense | $ 134,600 |  |  |
Recognition period (in years) | 2 years 3 months 18 days |  |  |

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