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
Net loss	$ (44,492)	$ (44,465)	$ (90,844)	$ (88,319)
Other comprehensive income (loss):
Net unrealized gains (losses) on marketable debt securities available-for-sale	14	(33)	22	(34)
Foreign currency translation adjustment	(2,116)	1,765	(2,578)	2,245
Other comprehensive income (loss)	(2,102)	1,732	(2,556)	2,211
Comprehensive loss	$ (46,594)	$ (42,733)	$ (93,400)	$ (86,108)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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