Stock-Based Compensation - Compensation Expense (Details) - USD ($) $ in Thousands		12 Months Ended
	Dec. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Employee and non-employee stock options
Stock based compensation expense
Options granted (in shares)		2,558,000
Stock based compensation expense		$ 10,601	$ 7,326	$ 5,157
Unrecognized compensation expense	$ 19,400	$ 19,400
Unrecognized compensation expense recognized over weighted average period		2 years 9 months 18 days
Employee and non-employee stock options | Cost of product, licensing and other revenues
Stock based compensation expense
Stock based compensation expense		$ 641	592	291
Employee and non-employee stock options | Research and development
Stock based compensation expense
Stock based compensation expense		2,853	1,575	1,593
Employee and non-employee stock options | Selling, general and administrative
Stock based compensation expense
Stock based compensation expense		7,107	5,159	3,273
Employee stock options
Stock based compensation expense
Stock based compensation expense		10,317	6,910	5,005
Employee stock options | Cost of product, licensing and other revenues
Stock based compensation expense
Stock based compensation expense		651	351	262
Employee stock options | Research and development
Stock based compensation expense
Stock based compensation expense		2,829	1,566	1,563
Employee stock options | Selling, general and administrative
Stock based compensation expense
Stock based compensation expense		$ 6,837	4,993	3,180
Non-employee stock options
Stock based compensation expense
Options granted (in shares)	141,046
Options unvested (in shares)	10,456	10,456
Stock based compensation expense		$ 284	416	152
Non-employee stock options | Cost of product, licensing and other revenues
Stock based compensation expense
Stock based compensation expense		(10)	241	29
Non-employee stock options | Research and development
Stock based compensation expense
Stock based compensation expense		24	9	30
Non-employee stock options | Selling, general and administrative
Stock based compensation expense
Stock based compensation expense		$ 270	$ 166	$ 93