Summary of Significant Accounting Policies (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 29, 2012	Oct. 01, 2011	Sep. 29, 2012	Oct. 01, 2011
Schedule of basic and diluted earnings per common share
Net income	$ 8,835	$ 11,394	$ 30,704	$ 31,604
Weighted average basic shares outstanding	25,989	25,652	25,904	25,613
Basic net income per common share	$ 0.34	$ 0.44	$ 1.19	$ 1.23
Effect of dilutive stock options	10	49	32	40
Weighted average diluted shares outstanding	25,999	25,701	25,937	25,653
Diluted net income per common share	$ 0.34	$ 0.44	$ 1.18	$ 1.23