Consolidated Statements of Income (USD $) In Thousands, except Share data	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Income Statement [Abstract]
Net sales	$ 327,950	$ 281,892	$ 646,703	$ 560,029
Cost of sales	207,361	177,821	410,537	355,844
Selling and administrative expenses	87,067	80,389	173,196	160,836
Total operating costs and expenses	294,428	258,210	583,733	516,680
Operating income	33,522	23,682	62,970	43,349
Interest expense	2,364	4,978	6,032	10,097
Other expense (income), net	298	1,065	802	1,387
Income before income taxes	30,860	17,639	56,136	31,865
Income taxes	8,528	2,815	14,732	5,213
Net income	$ 22,332	$ 14,824	$ 41,404	$ 26,652
Per common share: [Abstract]
Basic	$ 0.40	$ 0.27	$ 0.75	$ 0.48
Diluted	$ 0.40	$ 0.26	$ 0.74	$ 0.47
Dividends	$ 0.08	$ 0.08	$ 0.16	$ 0.16
Weighted average common shares outstanding: [Abstract]
Basic	55,414,347	55,546,969	55,067,079	55,470,721
Diluted	56,288,447	56,339,770	55,948,098	56,152,953