Unaudited 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
Statement of Comprehensive Income [Abstract]
Net loss	$ (31,262)	$ (21,436)	$ (64,090)	$ (52,398)
Other comprehensive (loss) income:
Foreign currency translation	(1,995)	576	(1,340)	1,156
Other comprehensive (loss) income	(1,995)	576	(1,340)	1,156
Comprehensive loss	$ (33,257)	$ (20,860)	$ (65,430)	$ (51,242)

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

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