CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Sep. 27, 2014	Dec. 28, 2013
Accounts receivable, reserve for doubtful accounts	$ 8,117	$ 6,987
Property, plant and equipment, accumulated depreciation	$ 75,893	$ 73,329
Preferred stock, par value (in usd per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	2,000,000	2,000,000
Preferred stock, shares issued
Common stock, par value (in usd per share)	$ 0.01	$ 0.01
Common stock, shares authorized	47,500,000	47,500,000
Common stock, shares issued	23,906,472	23,786,203
Treasury stock, shares	4,816,912	4,661,701