Consolidated Statements of Income (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 29, 2013	Mar. 30, 2012
Net sales	$ 299,169	$ 353,630
Cost of sales	250,830	304,212
Gross margin	48,339	49,418
Selling, general and administrative expense	32,780	32,654
Research and development expense	3,557	3,092
Other-net	2,480	3,788
Operating profit	9,522	9,884
Interest expense-net	828	698
Income before income taxes	8,694	9,186
Income tax expense	1,909	3,068
Net income	$ 6,785	$ 6,118
Basic earnings per share:
Net income per share of common stock	$ 0.33	$ 0.30
Diluted earnings per share:
Net income per share of common stock	$ 0.33	$ 0.30
Cash dividends per share	$ 0.075	$ 0
Weighted-average number of shares of common stock outstanding:
Basic (in shares)	20,481	20,370
Diluted (in shares)	20,824	20,707