UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Comprehensive Income [Abstract]
Net (loss)	$ (30,338)	$ (7,587)	$ (91,351)	$ (5,796)
Other comprehensive (loss), net of tax
Unrealized (loss) gain on available-for-sale marketable securities	(216)	(162)	396	(277)
Foreign currency translation adjustments	(2,201)	(1,934)	(983)	(4,898)
Total other comprehensive (loss), net of tax	(2,417)	(2,096)	(587)	(5,175)
Comprehensive (loss)	$ (32,755)	$ (9,683)	$ (91,938)	$ (10,971)

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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