Quarterly Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Net sales	$ 176,924	$ 134,398	$ 115,227	$ 92,946	$ 114,930	$ 124,662	$ 99,833	$ 62,432	$ 519,495	$ 401,857	$ 269,311
Income (loss) from operations	29,952	15,935	5,497	(6,649)	(3,595)	(12,710)	(1,352)	(3,703)	44,735	(21,360)	$ 25,864
Net income (loss)	$ 8,059	$ 9,776	$ 3,403	$ (6,138)	$ (4,146)	$ (7,105)	$ (1,046)	$ (3,290)	$ 15,100	$ (15,587)
Earnings (loss) per share:
Basic (in usd per share)	$ 0.29	$ 0.35	$ 0.12	$ (0.22)	$ (0.15)	$ (0.25)	$ (0.04)	$ (0.12)	$ 0.54	$ (0.56)	$ 0.54
Dilutive (in usd per share)	$ 0.28	$ 0.34	$ 0.12	$ (0.22)	$ (0.15)	$ (0.25)	$ (0.04)	$ (0.12)	$ 0.53	$ (0.56)	$ 0.54
Weighted average common shares:
Basic (in shares)	27,969	27,969	27,963	28,059	28,061	28,125	28,126	27,710	27,996	28,006	28,773
Diluted (in shares)	28,781	28,381	28,213	28,059	28,061	28,125	28,126	27,710	28,407	28,006	29,089