Selected Quarterly Financial Data (Unaudited) (Schedule of Quarterly Financial Information) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Quarterly Financial Information Disclosure [Abstract]
Net sales	$ 55,171	$ 56,568	$ 70,997	$ 60,271	$ 57,063	$ 69,056	$ 66,071	$ 63,737	$ 243,007	$ 255,927	$ 202,643
Gross margin	5,854	5,308	9,106	7,370	6,424	10,425	11,695	9,272	27,638	37,816	23,034
Operating income	602	783	3,502	2,404	865	5,294	5,846	4,065	7,291	16,070	4,237
Provision (benefit) for income taxes	(557)	(577)	384	248	(441)	460	1,139	777	(502)	1,935	(7,601)
Net income	$ 200	$ 767	$ 2,086	$ 1,222	$ 583	$ 3,916	$ 4,038	$ 2,125	$ 4,275	$ 10,662	$ 7,610
Net income per common share - Basic	$ 0.02	$ 0.09	$ 0.24	$ 0.14	$ 0.07	$ 0.45	$ 0.52	$ 0.29	$ 0.49	$ 1.31	$ 1.05
Net income per common share - Diluted	$ 0.02	$ 0.09	$ 0.24	$ 0.14	$ 0.07	$ 0.44	$ 0.50	$ 0.28	$ 0.48	$ 1.28	$ 1.03