Selected Quarterly Financial Information (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Selected Quarterly Financial Information (unaudited)
Net sales	$ 106,849	$ 132,715	$ 136,547	$ 139,909	$ 191,685	$ 267,959	$ 264,815	$ 254,676	$ 516,020	$ 979,135	$ 930,892
Gross profit	38,727	49,884	61,254	65,268	83,088	124,934	135,349	130,963	215,133	474,334	449,485
Income (loss) from continuing operations, net of income taxes	(8,642)	7,698	11,011	16,462	23,588	52,617	56,318	57,979	26,529	190,502	277,176
(Loss) income from discontinued operations, net of income taxes	(413)	4,055	807	(50)	(3,312)	(16,754)	(37,112)	(5,337)	4,399	(62,515)	84,584
Net income	$ (9,055)	$ 11,753	$ 11,818	$ 16,412	$ 20,276	$ 35,863	$ 19,206	$ 52,642	$ 30,928	$ 127,987	$ 361,760
Basic:
Continuing operations (in dollars per share)	$ (0.22)	$ 0.20	$ 0.29	$ 0.43	$ 0.62	$ 1.34	$ 1.37	$ 1.46	$ 0.69	$ 4.80	$ 7.02
Discontinued operations (in dollars per share)	$ (0.01)	$ 0.10	$ 0.02		$ (0.09)	$ (0.43)	$ (0.90)	$ (0.14)	$ 0.11	$ (1.57)	$ 2.14
Income (in dollars per share)	$ (0.23)	$ 0.30	$ 0.31	$ 0.43	$ 0.53	$ 0.91	$ 0.47	$ 1.32	$ 0.80	$ 3.23	$ 9.16
Diluted :
Continuing operations (in dollars per share)	$ (0.22)	$ 0.20	$ 0.28	$ 0.42	$ 0.61	$ 1.31	$ 1.31	$ 1.36	$ 0.68	$ 4.63	$ 6.52
Discontinued operations (in dollars per share)	$ (0.01)	$ 0.10	$ 0.02		$ (0.09)	$ (0.41)	$ (0.86)	$ (0.12)	$ 0.11	$ (1.52)	$ 1.99
Income (in dollars per share)	$ (0.23)	$ 0.30	$ 0.30	$ 0.42	$ 0.52	$ 0.90	$ 0.45	$ 1.24	$ 0.79	$ 3.11	$ 8.51
Weighted average shares outstanding:
Basic (in shares)	38,698	38,577	38,370	38,261	38,212	39,335	40,998	39,842	38,477	39,658	39,499
Diluted (in shares)	38,698	39,169	38,988	38,863	38,771	40,069	43,002	42,531	39,051	41,155	42,514