Quarterly Financial Information (Unaudited) (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 revenues	$ 158,356	$ 212,575	$ 204,625	$ 164,262	$ 163,266	$ 163,260	$ 150,329	$ 104,528	$ 739,818	$ 581,383	$ 487,582
Gross profit (loss)	13,811	51,993	42,897	12,983	23,483	21,141	18,367	(825)	121,684	62,166	46,516
Net income (loss)	$ (13,747)	$ 27,121	$ 17,784	$ (2,560)	$ 50,580	$ 2,290	$ (6,403)	$ (16,415)	$ 28,598	$ 30,052	$ (81,445)
Basic earnings (loss) per common share (in dollars per share)	$ (0.09)	$ 0.18	$ 0.12	$ (0.02)	$ 0.34	$ 0.02	$ (0.04)	$ (0.11)	$ 0.19	$ 0.20	$ (0.73)
Diluted earnings (loss) per common share (in dollars per share)	$ (0.09)	$ 0.18	$ 0.12	$ (0.02)	$ 0.34	$ 0.02	$ (0.04)	$ (0.11)	$ 0.19	$ 0.20	$ (0.73)
Income tax benefit due to U.S. tax law changes					$ 51,600