Earnings (Loss) Per Share (Details) (USD $)
In Thousands, except Share data, unless otherwise specified
3 Months Ended 9 Months Ended
Sep. 28, 2012
Sep. 23, 2011
Sep. 28, 2012
Sep. 23, 2011
Computation of basic and diluted net income (loss) per share:        
Net income (loss) $ 3,816 $ (1,185) $ 10,907 $ 2,487
Net income (loss) per share:        
Basic $ 0.18 $ (0.06) $ 0.53 $ 0.15
Diluted $ 0.18 $ (0.06) $ 0.52 $ 0.15
Weighted average common shares outstanding:        
Basic 20,662,956 18,696,304 20,571,848 16,547,077
Diluted 20,980,019 18,696,304 20,911,337 17,024,121