Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenues:
Product revenue, net	$ 355
Operating expenses:
Cost of sales	4
Research and development	51,231	$ 41,314	$ 32,691
Selling, general and administrative	78,801	28,466	13,372
Total operating expenses	130,036	69,780	46,063
Loss from operations	(129,681)	(69,780)	(46,063)
Other income (expense):
Interest income	3,718	1,521	1,246
Interest expense	(11,268)	(1,748)	(571)
Other expense	(250)	(1,887)	(927)
Total other income (expense)	(7,800)	(2,114)	(252)
Net loss	$ (137,481)	$ (71,894)	$ (46,315)
Net loss per common share, basic and diluted	$ (4.16)	$ (2.84)	$ (2.15)
Weighted average common shares outstanding, basic and diluted	33,027	25,297	21,497
Other comprehensive income (loss) :
Unrealized gains (losses) from available-for-sale securities, net of tax of $0	$ (336)	$ 26	$ (92)
Total other comprehensive income (loss)	(336)	26	(92)
Comprehensive loss	$ (137,817)	$ (71,868)	$ (46,407)