Consolidated Statements of Income - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Statement [Abstract]
Net sales	$ 291,434	$ 317,659	$ 906,949	$ 951,832
Cost of sales	191,132	206,410	593,609	632,671
Selling and administrative expenses	56,555	60,364	175,049	187,770
Total operating costs and expenses	247,687	266,774	768,658	820,441
Operating income	43,747	50,885	138,291	131,391
Interest expense	2,637	2,435	7,944	8,558
Other (income) expense, net	(545)	741	(228)	1,768
Income from continuing operations before income taxes	41,655	47,709	130,575	121,065
Income taxes	7,984	13,407	33,601	33,782
Income from continuing operations	33,671	34,302	96,974	87,283
Loss from discontinued operations, net of income taxes	0	(425)	0	(425)
Net income	$ 33,671	$ 33,877	$ 96,974	$ 86,858
Basic:
Income from continuing operations (in dollars per share)	$ 0.61	$ 0.63	$ 1.76	$ 1.60
Loss from discontinued operations, net of income taxes (in dollars per share)	0.00	(0.01)	0.00	(0.01)
Basic (in dollars per share)	0.61	0.62	1.76	1.59
Diluted:
Income from continuing operations (in dollars per share)	0.61	0.62	1.74	1.57
Loss from discontinued operations, net of income taxes (in dollars per share)	0.00	(0.01)	0.00	(0.01)
Diluted (in dollars per share)	0.61	0.61	1.74	1.56
Dividends (in dollars per share)	$ 0.12	$ 0.11	$ 0.36	$ 0.33
Weighted average common shares outstanding:
Basic (in shares)	55,199,315	54,879,329	55,140,774	54,756,794
Diluted (in shares)	55,588,092	55,509,658	55,647,971	55,803,370