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
Condensed Consolidated Statements of Comprehensive Loss
Net loss	$ (71,420)	$ (75,193)	$ (161,690)	$ (156,783)
Net changes related to available-for-sale investment debt securities:
Unrealized gains (losses) on investment debt securities	392	(125)	1,195	249
Reclassification adjustment for realized gains on investment debt securities included in other income, net			4
Net unrealized gains (losses) on investment debt securities	392	(125)	1,199	249
Foreign currency translation gains (losses)	(59)	(1,559)	224	(1,042)
Other comprehensive (loss) income	333	(1,684)	1,423	(793)
Comprehensive loss	$ (71,087)	$ (76,877)	$ (160,267)	$ (157,576)

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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