Leases - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jan. 01, 2019
Lessee, Lease, Description [Line Items]
Operating lease, right-of-use asset	$ 53,451	$ 51,675
Operating lease liability	54,227
Rent expense	$ 13,000	$ 13,400	$ 12,500
Accounting Standards Update 2016-02
Lessee, Lease, Description [Line Items]
Operating lease, right-of-use asset				$ 54,000