Note 12 - Business Divestitures (Details Textual) $ in Thousands		3 Months Ended
Jun. 24, 2021 USD ($)	Mar. 26, 2022 USD ($)	Mar. 27, 2021 USD ($)
Gain (Loss) on Disposition of Business		$ (0)	$ (115)
Number of Reportable Segments	2	1
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] \| PCB Test Business [Member]
Proceeds from Sales of Business, Affiliate and Productive Assets	$ 125,100
Gain (Loss) on Disposition of Business	70,800
Disposal Group, Including Discontinued Operation, Assets, Total	48,200
Disposal Group, Including Discontinued Operation, Goodwill	21,900
Disposal Group, Including Discontinued Operation, Intangible Assets	$ 14,800

Amount classified as assets attributable to disposal group held for sale or disposed of.

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