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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Number of additional shares authorized for issuance under share-based payment arrangement.

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Number of shares issued under share-based payment arrangement.

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Percentage of vesting of award under share-based payment arrangement.

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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		12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2020	Dec. 31, 2022
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares)	6,400,000		6,400,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized	3,945,902
Potential Class A Shares associated with 2020 PSU grant performance criteria	90,000		90,000
PSU outstanding subject only to qualified retirement (in shares)	45,000		45,000
Shares paid for tax withholding for share based compensation (in shares)			187,287
Share-Based Payment Arrangement, Decrease for Tax Withholding Obligation	$ 0	$ 334	$ 6,758	$ 7,754
Class A Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares delivered			45,000
Shares paid for tax withholding for share based compensation (in shares)			187,287
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)			517,386
Unvested - Number of awards (in shares)	5,353,326		5,353,326			5,396,343
Unrecognized compensation expense	$ 68,100		$ 68,100
Recognition period (in years)			3 years 2 months 12 days
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period (in years)			3 years
Award vesting rights			50.00%
Granted - Number of awards (in shares)			0		60,000
Unvested - Number of awards (in shares)	216,170		216,170			231,170
Unrecognized compensation expense	$ 4,100		$ 4,100
Recognition period (in years)			2 years
Performance Shares \| Potential Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested - Number of awards (in shares)	264,143		264,143
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted - Number of awards (in shares)			515,702
Restricted Stock Units RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted - Number of awards (in shares)			1,684
Long-Term Cash Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Franchise capital award liability	$ 23,600		$ 23,600			$ 14,500
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	39,000		$ 39,000
Deferred Bonus
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense	$ 80,600		$ 80,600
Recognition period (in years)			3 years 9 months 18 days