Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Condensed Consolidated Statements of Comprehensive Loss
Net Loss	$ (34,146)	$ (25,182)	$ (64,054)	$ (49,176)
Other comprehensive income (loss), net of tax
Foreign currency translation adjustments	(2,288)	(879)	1,104	(1,147)
Unrealized pension actuarial gains (losses), net of tax	256	626	32	223
Total other comprehensive loss, net of tax	$ (36,178)	$ (25,435)	$ (62,918)	$ (50,100)