Unaudited Quarterly Financial Data Unaudited Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Quarterly Financial Data [Abstract]
Net sales	$ 747,574	$ 821,204	$ 797,547	$ 727,418	$ 510,162	$ 416,471	$ 357,287	$ 292,826	$ 3,093,743	$ 1,576,746	$ 1,311,498
Gross profit	180,727	202,966	191,655	166,617	113,794	97,101	83,818	66,697	741,965	361,410	295,074
Net income (loss)	$ 10,418	$ 9,236	$ 17,982	$ (6,756)	$ (7,442)	$ 4,047	$ 2,125	$ (3,561)	$ 30,880	$ (4,831)	$ 94,032
Basic income (loss) per share
Net income (loss) per share (in dollars per share)	$ 0.16	$ 0.14	$ 0.27	$ (0.10)	$ (0.16)	$ 0.10	$ 0.05	$ (0.09)	$ 0.47	$ (0.12)	$ 2.42
Diluted income (loss) per share
Net income (loss) per share (in dollars per share)	$ 0.16	$ 0.14	$ 0.27	$ (0.10)	$ (0.16)	$ 0.10	$ 0.05	$ (0.09)	$ 0.46	$ (0.12)	$ 2.39