UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (32,296)	$ (10,409)	$ (61,013)	$ 1,791
Other comprehensive (loss) income, net of tax
Unrealized gain (loss) on available-for-sale marketable securities	238	73	612	(115)
Foreign currency translation adjustments	(409)	(7,414)	1,218	(2,964)
Total other comprehensive (loss) income, net of tax	(171)	(7,341)	1,830	(3,079)
Comprehensive (loss)	$ (32,467)	$ (17,750)	$ (59,183)	$ (1,288)

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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