Revenue Recognition - Schedule of Graduation Fund liability (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Graduation Fund [Roll Forward]
Balance at beginning of period	$ 44,480	$ 46,842
Revenue deferred	3,134	4,652
Benefit redeemed	(5,527)	(5,574)
Balance at end of period	$ 42,087	$ 45,920