Note 4 - Restructuring Charges - Charges Related to the Wind Down Plan (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 24, 2022	Sep. 25, 2021	Sep. 24, 2022	Sep. 25, 2021
Costs accrued	$ 17	$ 31	$ 600	$ 1,988
Integration Program [Member]
Costs accrued			600	2,000
Integration Program [Member] | Employee Severance [Member]
Accrued restructuring, beginning balance			348	5,826
Costs accrued			(15)	1,124
Amounts paid or charged			(269)	(6,410)
Impact of currency exchange			(9)	(83)
Accrued restructuring, ending balance	55	457	55	457
Integration Program [Member] | Other Restructuring [Member]
Accrued restructuring, beginning balance			0	0
Costs accrued			615	864
Amounts paid or charged			(615)	(864)
Impact of currency exchange			0	0
Accrued restructuring, ending balance	0	0	0	0
Integration Program [Member] | Employee Severance and Other Exit Costs [Member]
Accrued restructuring, beginning balance			348	5,826
Costs accrued			600	1,988
Amounts paid or charged			(884)	(7,274)
Impact of currency exchange			(9)	(83)
Accrued restructuring, ending balance	$ 55	$ 457	$ 55	$ 457