Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Condensed Consolidated Statements of Comprehensive Loss
Net loss	$ (49,380)	$ (44,224)	$ (92,524)	$ (96,725)
Other comprehensive loss:
Unrealized gains (losses) on available-for-sale securities	47	17	35	(17)
Total other comprehensive income (loss)	47	17	35	(17)
Comprehensive loss	$ (49,333)	$ (44,207)	$ (92,489)	$ (96,742)

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

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