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Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

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Compensation and Benefits - Additional information (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Mar. 31, 2022	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares)		5,933,801
PSU outstanding subject only to qualified retirement (in shares)		35,252
Shares paid for tax withholding for share based compensation (in shares)		161,650
Share-Based Payment Arrangement, Decrease for Tax Withholding Obligation		$ 6,831	$ 6,758
Potential Class A Shares associated with 2020 PSU grant performance criteria		75,233
PSU outstanding subject only to qualified retirement		80,252		45,000
Share-Based Compensation Arrangement By Share-Based Payment Award, Award Requisite Service Period, Retirement Acceleration		18 months
Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares delivered		39,981
Shares paid for tax withholding for share based compensation (in shares)		149,172
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)		504,055
Unvested - Number of awards (in shares)		5,276,480		5,351,492
Unrecognized compensation expense		$ 59,300
Recognition period (in years)		2 years 9 months 18 days
Shares paid for tax withholding for share based compensation (in shares)		149,172
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)	75,230	0
Unvested - Number of awards (in shares)		176,192		216,170
Unrecognized compensation expense		$ 1,600
Recognition period (in years)		1 year 4 months 24 days
Adjustment for performance results achieved (in shares)		3
Performance Shares \| Potential Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested - Number of awards (in shares)		224,162
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted - Number of awards (in shares)		502,774
Restricted Stock Units RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted - Number of awards (in shares)		1,281
Long-Term Cash Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Franchise capital award liability		$ 52,300		$ 33,000
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		$ 38,400
Deferred Bonus
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense		$ 102,000
Recognition period (in years)		2 years 10 months 24 days