Significant Stock-Based Plan Activity and 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
Stock-Based Compensation Expense [Abstract]
Total Stock-based compensation expense	$ 371	$ 391	$ 1,058	$ 945
Unrecognized stock-based compensation expense	2,000		$ 2,000
Weighted average remaining vesting period			1 year 9 months
Cost of sales
Stock-Based Compensation Expense [Abstract]
Total Stock-based compensation expense	42	50	$ 108	86
Selling, general and administrative expense
Stock-Based Compensation Expense [Abstract]
Total Stock-based compensation expense	$ 329	$ 341	$ 950	$ 859