Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Mar. 24, 2015	Dec. 30, 2014
Consolidated Balance Sheets [Abstract]
Less accumulated depreciation	$ (61,971)	$ (58,443)
Preferred stock, par value per share	$ 0.001	$ 0.001
Preferred stock, shares authorized	10,000,000us-gaap_PreferredStockSharesAuthorized	10,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, shares issued	0us-gaap_PreferredStockSharesIssued	0us-gaap_PreferredStockSharesIssued
Preferred stock, shares outstanding	0us-gaap_PreferredStockSharesOutstanding	0us-gaap_PreferredStockSharesOutstanding
Common stock, par value per share	$ 0.001	$ 0.001
Common stock, shares authorized	190,000,000us-gaap_CommonStockSharesAuthorized	190,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	23,908,542us-gaap_CommonStockSharesIssued	23,908,542us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	23,443,046us-gaap_CommonStockSharesOutstanding	23,417,396us-gaap_CommonStockSharesOutstanding
Treasury stock, shares	465,496us-gaap_TreasuryStockShares	465,496us-gaap_TreasuryStockShares

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

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Face amount or stated value per share of common stock.

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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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