Note 7 - Fair Value of Assets and Liabilities (Details) - Assets Measured at Fair Value (USD $) In Thousands, unless otherwise specified	Sep. 27, 2014	Dec. 28, 2013
Note 7 - Fair Value of Assets and Liabilities (Details) - Assets Measured at Fair Value [Line Items]
Available-for-sale securities	$ 13,115	$ 12,286
Total	13,115	12,286
Fair Value, Inputs, Level 1 [Member]
Note 7 - Fair Value of Assets and Liabilities (Details) - Assets Measured at Fair Value [Line Items]
Available-for-sale securities	13,115	12,286
Total	$ 13,115	$ 12,286

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (aa)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6871852&loc=d3e26610-111562

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Balance Type:	debit
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