UNAUDITED 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)	$ (25,372)	$ (28,717)
Other comprehensive (loss) income, net of tax
Unrealized gain on available-for-sale securities	100	374
Foreign currency translation adjustments	(514)	1,627
Total other comprehensive (loss) income, net of tax	(414)	2,001
Comprehensive (loss)	$ (25,786)	$ (26,716)

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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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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