Earnings (Loss) Per Share (Details 1) (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
Numerator:        
Net income (loss) $ 3,816 $ (1,185) $ 10,907 $ 2,487
Denominator:        
Weighted average basic common shares outstanding 20,662,956 18,696,304 20,571,848 16,547,077
Dilutive effect of unvested common shares 317,063    339,489 477,044
Weighted average diluted common shares outstanding 20,980,019 18,696,304 20,911,337 17,024,121