Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 08, 2015	Dec. 30, 2014
Condensed Consolidated Balance Sheets [Abstract]
Less accumulated depreciation	$ (67,020)	$ (58,443)
Preferred stock, par value per share	$ 0.001	$ 0.001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value per share	$ 0.001	$ 0.001
Common stock, shares authorized	190,000,000	190,000,000
Common stock, shares issued	23,919,192	23,908,542
Common stock, shares outstanding	23,264,669	23,443,046
Treasury stock, shares	654,523	465,496