Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Net loss	$ (38,420)	$ (36,387)	$ (121,479)	$ (75,811)
Other comprehensive loss, before tax:
Unrealized gain (loss) on available-for-sale investments	1,952	476	4,128	(1,130)
Foreign currency translation gain	(82)	(18)	38	2
Comprehensive loss, before tax	(36,550)	(35,929)	(117,313)	(76,939)
Income tax expense related to items of other comprehensive loss	(464)		(984)
Comprehensive loss, net of tax	$ (37,014)	$ (35,929)	$ (118,297)	$ (76,939)

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

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