Consolidated Statements of Income (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Income Statement [Abstract]
Net sales	$ 578,157	$ 528,027	$ 1,738,911	$ 1,647,156
Cost of sales	415,600	376,526	1,243,427	1,168,687
Gross profit	162,557	151,501	495,484	478,469
Selling and administrative expenses	109,182	103,544	323,184	316,357
Goodwill impairment	0	6,946	0	6,946
Operating income	53,375	41,011	172,300	155,166
Interest expense, net	1,544	1,687	5,239	5,364
Income before income taxes and equity (loss) earnings	51,831	39,324	167,061	149,802
Provision for income taxes	19,496	17,965	64,808	60,020
Equity (loss) earnings in unconsolidated investments	(3)	16	52	187
Net income	$ 32,332	$ 21,375	$ 102,305	$ 89,969
Earnings per share:
Basic (in dollars per share)	$ 0.70	$ 0.46	$ 2.20	$ 1.91
Diluted (in dollars per share)	$ 0.68	$ 0.45	$ 2.14	$ 1.87
Weighted average shares outstanding: [Abstract]
Basic (in shares)	46,380	46,574	46,475	47,076
Diluted (in shares)	47,598	47,787	47,720	48,205
Cash dividends declared per common share	$ 0.19	$ 0.16	$ 0.54	$ 0.46