SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) (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	$ 86,367	$ 100,094	$ 110,954	$ 100,135	$ 90,318	$ 87,883	$ 80,915	$ 67,313	$ 397,550	$ 326,429	$ 192,803
Gross profit	30,221	36,224	42,073	36,405	31,439	29,728	26,775	22,753	144,923	110,695	59,391
Net income (loss)	$ (5,288)	$ 6,915	$ 17,244	$ 15,170	$ 15,271	$ 4,910	$ 6,372	$ 3,920	$ 34,041	$ 30,473	$ (18,853)
Net income per share
Basic (in dollars per share)	$ (0.36)	$ 0.47	$ 1.17	$ 1.02	$ 1.02	$ 0.33	$ 0.43	$ 0.26	$ 2.29	$ 2.05	$ (1.31)
Diluted (in dollars per share)	$ (0.36)	$ 0.46	$ 1.15	$ 1.01	$ 1.02	$ 0.33	$ 0.43	$ 0.26	$ 2.28	$ 2.04	$ (1.31)