Inventories (Details) (USD $) In Thousands, unless otherwise specified	Mar. 30, 2013	Dec. 29, 2012
Inventories
Finished goods	$ 8,410	$ 9,469
Raw materials	13,663	17,602
Total inventories	$ 22,073	$ 27,071

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

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

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-Name Accounting Standards Codification

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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