Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 59,848	$ 44,024	$ 16,736
Foreign currency translation adjustment	1,142	514	(3,099)
Net unrealized (losses)/gains on derivatives, net of taxes	(382)	1,418	811
Other Comprehensive Income Loss Other Adjustment Net Of Tax	0	0	7
Other comprehensive income	760	1,932	(2,281)
Comprehensive income	$ 60,608	$ 45,956	$ 14,455