Note 6 - Goodwill, Intangible Assets and Long Term Assets - Amortization Expense for Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 01, 2017	Sep. 25, 2016	Oct. 01, 2017	Sep. 25, 2016
Amortization of Intangible Assets	$ 106	$ 129	$ 315	$ 403
Research and Development Expense [Member]
Amortization of Intangible Assets	42	49	123	152
Selling, General and Administrative Expenses [Member]
Amortization of Intangible Assets	$ 64	$ 80	$ 192	$ 251

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Balance Type:	debit
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