Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Operating expenses
Selling, general and administrative	$ 27,823	$ 14,475
Research and development	12,972	10,954
Total operating expenses	40,795	25,429
Loss from operations	(40,795)	(25,429)
Other income (expense), net	96	(312)
Net loss before income taxes	(40,699)	(25,741)
Income tax expense	0	46
Net loss	$ (40,699)	$ (25,787)
Net loss per common share—basic and diluted (in dollars per share)	$ (1.05)	$ (0.76)
Weighted average number of common shares outstanding—basic and diluted (in shares)	38,598,827	33,777,395
Net loss	$ (40,699)	$ (25,787)
Unrealized loss on available-for-sale investments	(129)	(37)
Comprehensive loss	$ (40,828)	$ (25,824)

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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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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Average number of shares or units issued and outstanding that are used in calculating basic and diluted earnings per share (EPS).

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