CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (18,792)	$ (13,885)
Other comprehensive income (loss)
Unrealized gains (losses) on available-for-sale investments, net of taxes	211	(329)
Comprehensive loss	$ (18,581)	$ (14,214)

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

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