Condensed Consolidated Statements Of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Statement [Abstract]
Net sales	$ 1,139,643	$ 1,203,525	$ 2,807,023	$ 2,934,355
Cost of goods sold	957,704	1,018,419	2,383,500	2,493,355
Gross profit	181,939	185,106	423,523	441,000
Selling, general and administrative expenses	51,711	54,113	162,092	162,969
Rationalization charges	7,821	9,070	13,929	10,754
Income from operations	122,407	121,923	247,502	267,277
Interest and other debt expense	17,318	17,159	50,657	50,364
Income before income taxes	105,089	104,764	196,845	216,913
Provision for income taxes	35,319	34,448	67,190	71,047
Net income	$ 69,770	$ 70,316	$ 129,655	$ 145,866
Earnings per share:
Basic net income per share	$ 1.15	$ 1.16	$ 2.14	$ 2.38
Diluted net income per share	1.15	1.16	2.13	2.37
Dividends per share	$ 0.17	$ 0.16	$ 0.51	$ 0.48
Weighted average number of shares:
Basic (in shares)	60,445	60,417	60,467	61,222
Effect of dilutive securities (in shares)	384	279	371	271
Diluted (in shares)	60,829	60,696	60,838	61,493