Consolidated Statement of Operations and Comprehensive Loss (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cost of product revenue, related party activity	$ 191	$ 235	$ 322
Stock compensation expense in cost of goods sold	228	76	18
Stock compensation expense in research and development expenses	513	180	59
Stock compensation expense in selling, general and administrative expenses	4,143	1,912	851
Product revenue
Related party revenue	294	339	509
Service and other revenue
Related party revenue	149	165	107
Collaboration and license revenue
Related party revenue	$ 2,150	$ 1,074	$ 172