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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