Condensed Consolidated Statements of Income (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Condensed Consolidated Statements of Income [Abstract]
Net sales	$ 182,374	$ 176,780	$ 581,894	$ 589,892
Cost of sales	149,187	142,523	438,528	429,695
Gross profit	33,187	34,257	143,366	160,197
Selling, general and administrative expense	21,711	21,635	65,988	64,737
Provisions for (recoveries of) losses on accounts receivable	(308)	39	(185)	160
Other expense	384	149	1,106	2,532
Other income	(489)	(58)	(837)	(2,035)
Operating income	11,889	12,492	77,294	94,803
Interest expense	1,489	1,901	3,800	5,481
Losses on extinguishment of debt				136
Non-operating other expense (income), net	2	2	(270)	(3)
Income from continuing operations before provisions for income taxes and equity in earnings and losses of affiliate	10,398	10,589	73,764	89,189
Provisions for income taxes	3,857	4,433	27,110	33,582
Equity in earnings of affiliate	(169)	(168)	(510)	(375)
Income from continuing operations	6,710	6,324	47,164	55,982
Net loss from discontinued operations	2	18	120	128
Net income	6,708	6,306	47,044	55,854
Dividends on preferred stocks			300	305
Net income applicable to common stock	$ 6,708	$ 6,306	$ 46,744	$ 55,549
Weighted-average common shares:
Basic	22,374	22,241	22,346	21,851
Diluted	23,552	23,526	23,528	23,499
Basic:
Income from continuing operations	$ 0.30	$ 0.28	$ 2.10	$ 2.55
Net loss from discontinued operations			$ (0.01)	$ (0.01)
Net income	$ 0.30	$ 0.28	$ 2.09	$ 2.54
Diluted:
Income from continuing operations	$ 0.28	$ 0.27	$ 2.01	$ 2.40
Net loss from discontinued operations			$ (0.01)	$ (0.01)
Net income	$ 0.28	$ 0.27	$ 2.00	$ 2.39