Note 14 - Business Divestitures and Discontinued Operations (Details Textual) $ in Thousands			3 Months Ended		6 Months Ended	12 Months Ended
		Jun. 24, 2021 USD ($)	Sep. 25, 2021	Dec. 28, 2019 USD ($)	Dec. 25, 2021 USD ($)	Dec. 25, 2021 USD ($)	Dec. 26, 2020 USD ($)	Dec. 28, 2019 USD ($)
Gain (Loss) on Disposition of Business	[1]					$ 70,815	$ (0)	$ (0)
Disposal Group, Including Discontinued Operation, Assets, Total				$ 3,618	$ 0	$ 0	0	3,618
Number of Reportable Segments		2	1			1
Disposal Group, Including Discontinued Operation, Impairment							$ (0)	$ 1,086
Fixtures Services Business FSG [Member]
Disposal Group, Including Discontinued Operation, Impairment				$ 1,100
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	$ 48,200
Disposal Group, Including Discontinued Operation, Goodwill					21,900	21,900
Disposal Group, Including Discontinued Operation, Intangible Assets					$ 14,800	$ 14,800

[1] On June 24, 2021 we completed the divestment of our PCB Test business. The divestment of this business did not qualify for presentation as discontinued operations and the results of the PCB Test business are included in continuing operations for all periods presented. See Note 14, “Business Divestitures and Discontinued Operations” for additional information on this transaction and financial statement presentation.