Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 21, 2017	Dec. 27, 2016
Condensed Consolidated Balance Sheets [Abstract]
Property and equipment, accumulated depreciation	$ 92,930	$ 88,190
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	24,271,703	24,234,909
Common stock, shares outstanding	21,826,476	23,272,274
Treasury stock, shares	2,445,227	962,635

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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