Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Statement of Comprehensive Income [Abstract]
Net loss	$ (33,170)	$ (30,832)
Other comprehensive income (loss), net of tax:
Unrealized loss on interest rate swap	(9,527)	0
Foreign currency translation adjustments	777	(8)
Unrealized gain on available-for sale marketable securities, net of reclassification adjustments for realized amounts	0	13
Employee retirement benefits	0	32
Other comprehensive (loss) income, net of tax	(8,750)	37
Comprehensive loss	$ (41,920)	$ (30,795)