Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Consolidated Statements of Comprehensive Income
Net income	$ 170,358	$ 149,140	$ 121,506
Other comprehensive loss, net of income tax:
Foreign currency translation adjustment	24,861	(2,836)	(13,792)
Total comprehensive income	195,219	146,304	107,714
Total comprehensive income attributable to:
Stockholders	194,899	146,217	107,716
Non-controlling interests	320	87	(2)
Total comprehensive income	$ 195,219	$ 146,304	$ 107,714