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Compensation and Benefits - Change in Value of Investments (Details) - Long-Term Cash Awards - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Compensation and Benefits, Impact of Change in Value of Investments
Schedule of Investments [Line Items]
Long-term Incentive Compensation Expense, Impact of Change in Value of Investments	$ 213	$ 0	$ 210	$ 0
Other Net Investment Gain (Loss), Franchise Capital Awards
Schedule of Investments [Line Items]
Net investment gain (loss)	$ (2,578)	$ 0	$ (2,473)	$ 0

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Amount of realized and unrealized gain (loss) on investment.

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