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
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (12,387)	$ (22,675)	$ (27,270)	$ (53,060)
Other comprehensive income (loss):
Cumulative translation loss		(3)
Comprehensive loss	$ (12,387)	$ (22,678)	$ (27,270)	$ (53,060)

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

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