Note 4 - Purchased Intangible Assets, Subject to Amortization (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 26, 2015	Dec. 27, 2014
Rasco Technology [Member]
Gross Carrying Amount	$ 26,904	$ 29,845
Accumulated Amortization	$ 23,776	22,616
Finite-Lived Intangible Asset, Useful Life	328 days
Ismeca Technology [Member]
Gross Carrying Amount	$ 27,043	27,014
Accumulated Amortization	$ 10,329	6,879
Finite-Lived Intangible Asset, Useful Life	5 years
Trade Names [Member]
Gross Carrying Amount	$ 5,547	$ 5,723
Accumulated Amortization	$ 92
Finite-Lived Intangible Asset, Useful Life	14 years 255 days
Gross Carrying Amount	$ 59,494	$ 62,582
Accumulated Amortization	$ 34,197	$ 29,495

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

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

+ References

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=26713463&loc=d3e16323-109275

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- Definition

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

+ References

+ Details

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- Details

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- Details

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- Details

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