CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (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 loss	$ (10,358)	$ (29,260)	$ (20,783)	$ (29,149)
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(5,566)	13,187	(14,111)	27,786
Total comprehensive loss	$ (15,924)	$ (16,073)	$ (34,894)	$ (1,363)