UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (28,717)	$ 12,200
Other comprehensive income, net of tax
Unrealized gain (loss) on available-for-sale marketable securities, net of tax	374	(188)
Foreign currency translation adjustments	1,627	4,450
Total other comprehensive income, net of tax	2,001	4,262
Comprehensive (loss) income	$ (26,716)	$ 16,462

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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