Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 28, 2015	Dec. 27, 2014
Consolidated Balance Sheets [Abstract]
Common Stock, No Par Value	$ 0us-gaap_CommonStockNoParValue	$ 0us-gaap_CommonStockNoParValue
Common Stock, Shares Authorized	100,800,000us-gaap_CommonStockSharesAuthorized	100,800,000us-gaap_CommonStockSharesAuthorized
Common Stock, Shares Issued	33,047,807us-gaap_CommonStockSharesIssued	33,047,807us-gaap_CommonStockSharesIssued
Common Stock, Shares Outstanding	26,898,443us-gaap_CommonStockSharesOutstanding	26,898,443us-gaap_CommonStockSharesOutstanding
Deferred Tax, Other Comprehensive Income	$ 3,381	$ 3,371
Treasury Stock, Shares	6,149,364us-gaap_TreasuryStockShares	6,149,364us-gaap_TreasuryStockShares

Face amount per share of no-par value common stock.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Amount of tax expense (benefit), after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities. Excludes amounts related to other than temporary impairment (OTTI) loss.

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Reference 1: 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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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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