CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - UNAUDITED - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 19,321	$ 10,366	$ 38,952	$ 31,880
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	2,212	2,671	1,857	(12,413)
Unrealized holding gains (losses) on short-term investments arising during period	(7)	52	(13)	28
Other comprehensive income (loss), net of tax	2,205	2,723	1,844	(12,385)
Total comprehensive income, net of tax	$ 21,526	$ 13,089	$ 40,796	$ 19,495