Note 2 - Intangible Assets - Amortizing Intangible Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 30, 2016
Gross carrying amount	$ 2,927	$ 2,927
Accumulated amortization	(1,357)	(1,213)
Net carrying amount	1,570	1,714
Patented Technology [Member]
Gross carrying amount	1,058	1,058
Accumulated amortization	(561)	(498)
Net carrying amount	497	560
Customer Lists [Member]
Gross carrying amount	1,869	1,869
Accumulated amortization	(796)	(715)
Net carrying amount	$ 1,073	$ 1,154

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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