Quarterly Financial Data (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								5 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, 2015	Dec. 31, 2017	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Net sales	$ 54,135	$ 60,772	$ 16,389	$ 32,730	$ 51,673	$ 61,200	$ 18,385	$ 28,411	$ 111,081	$ 164,026	$ 159,669
Cost of sales	11,290	11,620	3,906	5,839	11,791	8,905	15,833	23,820	91,752	32,655	59,977
Gross profit	42,845	49,152	12,483	26,891	39,882	52,295	2,552	4,591	19,329	131,371	99,692
(Loss) income before taxes	30,754	13,178	(14,302)	(10,647)	(29,595)	11,988	(40,790)	(40,426)
Net (loss) income	$ 23,438	$ 9,546	$ 2,607	$ (12,029)	$ (68,854)	$ 7,312	$ (25,164)	$ (25,137)	$ (14,437)	$ 23,471	$ (111,560)
Net (loss) income per common share:
Basic (in dollars per share)	$ 0.47	$ 0.19	$ 0.05	$ (0.24)	$ (1.40)	$ 0.15	$ (0.51)	$ (0.51)	$ (0.29)	$ 0.47	$ (2.26)
Diluted (in dollars per share)	$ 0.47	$ 0.19	$ 0.05	$ (0.24)	$ (1.40)	$ 0.15	$ (0.51)	$ (0.51)	$ (0.29)	$ 0.47	$ (2.26)