Stock‑Based Compensation (CompExp) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Employee and non-employee stock options
Stock based compensation expense
Stock based compensation expense	$ 7,326	$ 5,157	$ 1,657
Unrecognized compensation expense	$ 14,700
Unrecognized compensation expense recognized over weighted average period	1 year 11 months 16 days
Employee and non-employee stock options | Cost of revenues
Stock based compensation expense
Stock based compensation expense	$ 592	291	62
Employee and non-employee stock options | Research and development
Stock based compensation expense
Stock based compensation expense	1,575	1,593	616
Employee and non-employee stock options | Selling, general and administrative
Stock based compensation expense
Stock based compensation expense	5,159	3,273	979
Employee stock options
Stock based compensation expense
Stock based compensation expense	6,910	5,005	1,637
Employee stock options | Cost of revenues
Stock based compensation expense
Stock based compensation expense	351	262	55
Employee stock options | Research and development
Stock based compensation expense
Stock based compensation expense	1,566	1,563	612
Employee stock options | Selling, general and administrative
Stock based compensation expense
Stock based compensation expense	4,993	3,180	970
Non-employee stock options
Stock based compensation expense
Stock based compensation expense	416	152	20
Non-employee stock options | Cost of revenues
Stock based compensation expense
Stock based compensation expense	241	29	7
Non-employee stock options | Research and development
Stock based compensation expense
Stock based compensation expense	9	30	4
Non-employee stock options | Selling, general and administrative
Stock based compensation expense
Stock based compensation expense	$ 166	$ 93	$ 9