Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Statement [Abstract]
Revenue	$ 44	$ 236	$ 641
Operating expenses:
Research and development	29,153	11,434	1,595
Selling, general and administrative	95,391	227,678	4,621
Total operating expenses	124,544	239,112	6,216
Loss from operations	(124,500)	(238,876)	(5,575)
Other income (expense):
Investment income, net	3,097	2,988	20
Change in fair value of warrant liability	0	(1,366)	(158)
Interest expense	(66)	0	(471)
Other income, net	88	77	0
Total other income (expense)	3,119	1,699	(609)
Loss before income taxes	(121,381)	(237,177)	(6,184)
Income tax (benefit) expense, net	(572)	(301)	1
Net loss	$ (120,809)	$ (236,876)	$ (6,185)
Net loss per share:
Basic and diluted	$ (1.47)	$ (3.31)	$ (0.75)
Weighted average number of shares during the period:
Basic and diluted	81,979,005	71,519,609	8,246,028