Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Statement [Abstract]
Net sales	$ 3,612,914	$ 3,763,971	$ 3,911,790
Cost of goods sold	3,079,378	3,209,845	3,311,960
Gross profit	533,536	554,126	599,830
Selling, general and administrative expenses	214,745	219,907	224,496
Rationalization charges	19,061	14,407	14,481
Income from operations	299,730	319,812	360,853
Interest and other debt expense before loss on early extinguishment of debt	67,813	66,926	74,827
Loss on early extinguishment of debt	0	0	1,474
Interest and other debt expense	67,813	66,926	76,301
Income before income taxes	231,917	252,886	284,552
Provision for income taxes	78,566	80,473	102,161
Net income	$ 153,351	$ 172,413	$ 182,391
Basic net income per share (in dollars per share)	$ 2.56	$ 2.83	$ 2.88
Diluted net income per share (in dollars per share)	2.55	2.81	2.86
Dividends per share (in dollars per share)	$ 0.68	$ 0.64	$ 0.60