Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net loss	$ (35,202)	$ (30,180)
Other comprehensive income:
Change in unrealized gains on marketable securities	370	0
Comprehensive loss	$ (34,832)	$ (30,180)

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

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