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, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Net sales	$ 57,063	$ 69,056	$ 66,071	$ 63,737	$ 50,274	$ 50,887	$ 52,607	$ 48,875	$ 255,927	$ 202,643	$ 154,434
Gross margin	6,424	10,425	11,695	9,272	6,159	5,464	7,166	4,245	37,816	23,034	13,513
Operating (loss) income	865	5,294	5,846	4,065	1,038	1,016	2,667	(484)	16,070	4,237	(3,969)
Provision (benefit) for income taxes	(441)	460	1,139	777	(7,884)	176	369	(262)	1,935	(7,601)	(3,526)
Net (loss) income	$ 583	$ 3,916	$ 4,038	$ 2,125	$ 7,860	$ (259)	$ 1,228	$ (1,219)	$ 10,662	$ 7,610	$ (5,347)
Net (loss) income per common share - Basic	$ 0.07	$ 0.45	$ 0.52	$ 0.29	$ 1.09	$ (0.04)	$ 0.17	$ (0.17)	$ 1.31	$ 1.05	$ (0.74)
Net (loss) income per common share - Diluted	$ 0.07	$ 0.44	$ 0.50	$ 0.28	$ 1.06	$ (0.04)	$ 0.17	$ (0.17)	$ 1.28	$ 1.03	$ (0.74)