Condensed Consolidated Statements Of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Income Statement [Abstract]
Net sales	$ 592,172	$ 650,492
Cost of sales	459,578	509,759
Gross profit	132,594	140,733
Selling, general and administrative expenses	84,839	80,913
Operating profit	47,755	59,820
Interest expense, net	2,507	1,101
Income before income taxes	45,248	58,719
Provision for income taxes	10,882	11,383
Net income	$ 34,366	$ 47,336
Net income per common share:
Basic (in usd per share)	$ 1.38	$ 1.88
Diluted (in usd per share)	$ 1.38	$ 1.86
Weighted average common shares outstanding:
Basic (in shares)	24,914	25,149
Diluted (in shares)	24,929	25,465