Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 37,729	$ 30,518	$ 9,756
Other comprehensive income (loss), net of reclassification adjustments:
Unrealized gain (loss) on interest rate swap contracts, net of tax	(421)	(404)	1,245
Foreign currency translation adjustments	(4,320)	3,810	(8,034)
Other comprehensive gain (loss)	(4,741)	3,406	(6,789)
Comprehensive income	$ 32,988	$ 33,924	$ 2,967