Unaudited Condensed Consolidated Statements of Comprehensive Loss - 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	$ (22,862)	$ (83,528)	$ (73,177)	$ (104,122)
Foreign currency translation adjustment	516	3,850	(4,419)	10,406
Foreign currency hedge	97	(483)	464	(1,598)
Amortization of net actuarial loss on defined benefit pension plans	0	19	0	53
Other comprehensive income (loss), before tax	613	3,386	(3,955)	8,861
Tax (provision) benefit attributable to other comprehensive income (loss)	202	(1,065)	992	(2,295)
Other comprehensive income (loss), net of tax	815	2,321	(2,963)	6,566
Total comprehensive loss	$ (22,047)	$ (81,207)	$ (76,140)	$ (97,556)

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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