Stock-Based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated stock-based compensation expense	$ 1,525	$ 2,613	$ 8,811	$ 8,801
Cost of goods sold
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated stock-based compensation expense	111	169	614	642
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated stock-based compensation expense	146	328	841	911
Clinical and regulatory affairs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated stock-based compensation expense	(49)	107	383	527
Marketing and sales
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated stock-based compensation expense	685	874	2,505	3,215
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated stock-based compensation expense	632	1,135	4,468	3,506
Total operating expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated stock-based compensation expense	$ 1,414	$ 2,444	$ 8,197	$ 8,159