Unaudited Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net loss	$ (32,470)	$ (11,086)	$ (50,315)	$ (20,594)
Foreign currency translation adjustment	(4,809)	4,448	(4,935)	6,556
Foreign currency hedge	788	(949)	367	(1,115)
Amortization of net actuarial loss on defined benefit pension plans	0	17	0	34
Other comprehensive income (loss), before tax	(4,021)	3,516	(4,568)	5,475
Tax (provision) benefit attributable to other comprehensive income (loss)	560	(782)	790	(1,230)
Other comprehensive income (loss), net of tax	(3,461)	2,734	(3,778)	4,245
Total comprehensive loss	$ (35,931)	$ (8,352)	$ (54,093)	$ (16,349)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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