CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS
Net loss	$ (215,524)	$ (285,405)	$ (190,669)
Other comprehensive income (loss):
Net unrealized gain (loss) on available-for-sale investments, net of tax	567	(480)	(183)
Comprehensive loss	$ (214,957)	$ (285,885)	$ (190,852)

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

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