Stock-Based Compensation - Schedule of Stock Based Compensation Expense (Details) - USD ($) shares in Thousands, $ 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]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	932	597	739	995
Allocated Share-based Compensation Expense	$ 860	$ 809	$ 2,452	$ 2,621
Cost of product sales
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	40	68	122	222
Cost of service sales
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	0	0	0	1
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	177	155	496	514
Sales, marketing and support
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	138	190	485	679
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated Share-based Compensation Expense	$ 505	$ 396	$ 1,349	$ 1,205