Stock-based Compensation - Allocation of Recognized Period Costs (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated share-based compensation	$ 624	$ 520
Cost of goods sold
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated share-based compensation	123	93
Research and development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated share-based compensation	42	27
Selling, general, and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated share-based compensation	$ 459	$ 400