Balance Sheet Items (Schedule Of Inventory) (Details) (USD $)	Mar. 28, 2015	Dec. 27, 2014
Balance Sheet Items [Abstract]
Work-in-progress	$ 16,838,000us-gaap_InventoryWorkInProcess	$ 17,438,000us-gaap_InventoryWorkInProcess
Finished goods	18,847,000us-gaap_InventoryFinishedGoods	20,511,000us-gaap_InventoryFinishedGoods
Inventory, net	35,685,000us-gaap_InventoryNet	37,949,000us-gaap_InventoryNet
Inventory reserves	$ 7,500,000us-gaap_InventoryValuationReserves	$ 7,800,000us-gaap_InventoryValuationReserves

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

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-Name Accounting Standards Codification

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-Subparagraph (SX 210.5-02.6(a)(1))

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

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Amount of valuation reserve for inventory.

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

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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-Publisher SEC

-Name Regulation S-X (SX)

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