CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net loss	$ (41,420)	$ (52,709)
Other comprehensive income, net of taxes:
Change in unrealized gain (loss) on available-for-sale marketable securities	1,189	(1,127)
Change in foreign currency translation adjustment	1	68
Comprehensive loss	$ (40,230)	$ (53,768)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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