Condensed Consolidated Statements Of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income Statement [Abstract]
Net sales	$ 498,336	$ 422,798
Cost of sales	374,322	314,357
Gross profit	124,014	108,441
Selling, general and administrative expenses	64,885	52,713
Operating profit	59,129	55,728
Interest expense, net	437	476
Income before income taxes	58,692	55,252
Provision for income taxes	15,547	19,293
Net income	$ 43,145	$ 35,959
Net income per common share:
Basic (in usd per share)	$ 1.73	$ 1.46
Diluted (in usd per share)	$ 1.71	$ 1.45
Weighted average common shares outstanding:
Basic (in shares)	24,906	24,567
Diluted (in shares)	25,255	24,794