Quarterly Financial Data (Unaudited) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Quarterly Financial Data (Unaudited)
Net sales	$ 53,621	$ 116,020	$ 133,485	$ 61,067	$ 61,129	$ 129,240	$ 139,725	$ 54,569	$ 364,193	$ 384,663	$ 383,660
Gross profit	13,449	37,613	40,831	17,198	15,674	41,578	40,062	14,136
(Loss) income from continuing operations	(1,985)	11,600	6,840	(867)	(2,747)	12,109	10,314	(3,447)	15,588	16,229	17,194
(Loss) income from discontinued operations, net of tax	(416)	11	81	(37)	(477)	(1,131)	5,171	(4,122)	(361)	(559)	(11,583)
Net (loss) income	$ (2,401)	$ 11,611	$ 6,921	$ (904)	$ (3,224)	$ 10,978	$ 15,485	$ (7,569)	$ 15,227	$ 15,670	$ 5,611
Basic:
Continuing operations (1)	$ (0.21)	$ 1.21	$ 0.71	$ (0.09)	$ (0.28)	$ 1.25	$ 1.06	$ (0.35)	$ 1.63	$ 1.67	$ 1.77
Discontinued operations (1)	$ (0.04)	$ 0.00	$ 0.01	$ 0.00	$ (0.05)	$ (0.12)	$ 0.53	$ (0.42)	$ (0.04)	$ (0.06)	$ (1.19)
Total	$ (0.25)	$ 1.22	$ 0.72	$ (0.09)	$ (0.33)	$ 1.13	$ 1.59	$ (0.78)
Diluted:
Continuing operations (1)	$ (0.21)	$ 1.21	$ 0.71	$ (0.09)	$ (0.28)	$ 1.24	$ 1.06	$ (0.35)	$ 1.63	$ 1.67	$ 1.77
Discontinued operations (1)	$ (0.04)	$ 0.00	$ 0.01	$ 0.00	$ (0.05)	$ (0.12)	$ 0.53	$ (0.42)	$ (0.04)	$ (0.06)	$ (1.19)
Total	$ (0.25)	$ 1.22	$ 0.72	$ (0.09)	$ (0.33)	$ 1.13	$ 1.59	$ (0.78)