Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Consolidated Statements of Comprehensive Income (Unaudited) [Abstract]
Net income	$ 46,349	$ 50,961	$ 89,351	$ 86,500
Other comprehensive income, net of tax:
Foreign currency translation adjustment, net of taxes of $362 and $(558) for the three months ended June 30, 2019 and 2018, respectively, and $217 and $296 for the six months ended June 30, 2019 and 2018, respectively	(5,482)	(20,047)	(1,342)	(9,000)
Net unrealized gains/(losses) on foreign currency cash flow hedges, net of taxes of zero and $(10) for the three months ended June 30, 2019 and 2018, respectively, and zero and $18 for the six months ended June 30, 2019 and 2018, respectively	0	87	0	(160)
Reclassification adjustment for realized losses/(gains) in current earnings, net of taxes of zero and $3 for the three months ended June 30, 2019 and 2018, respectively, and zero and $(2) for the six months ended June 30, 2019 and 2018, respectively	0	(26)	0	18
Other comprehensive income	(5,482)	(19,986)	(1,342)	(9,142)
Comprehensive income	$ 40,867	$ 30,975	$ 88,009	$ 77,358