Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 29,281	$ 24,538	$ 84,808	$ 75,058
Other comprehensive income (loss):
Foreign currency translation adjustments	(30,873)	659	(61,810)	3,917
Total other comprehensive (loss) income	(30,873)	659	(61,810)	3,917
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	(1,592)	25,197	22,998	78,975
Net Income (Loss) Attributable to Noncontrolling Interest	39	354	178	1,013
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ (1,631)	$ 24,843	$ 22,820	$ 77,962