Accrued Expenses - Summary of Accrued Expenses (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Payables and Accruals [Abstract]
Accrued compensation	$ 25,190	$ 15,959
Accrued Cost Of Revenues Current	10,341	10,834
Accrued interest	4,844	11
Accrued IPO offering expenses	1,424
Other accrued expenses	11,038	9,095
Total accrued expenses	$ 52,837	$ 35,899