Note 4 - Restructuring Charges - Charges Related to the Wind Down Plan (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019
Restructuring Charges, Total	$ 412	$ 814	$ 1,400	$ 10,720
Integration Program [Member]
Restructuring Charges, Total			1,400	10,700
Integration Program [Member] \| Employee Severance [Member]
Accrued restructuring, beginning balance			1,236	4,026
Restructuring Charges, Total			287	10,167
Amounts paid or charged			(1,516)	(9,251)
Impact of currency exchange			0	(137)
Accrued restructuring, ending balance	7	4,805	7	4,805
Integration Program [Member] \| Other Restructuring [Member]
Accrued restructuring, beginning balance			0	0
Restructuring Charges, Total			1,113	553
Amounts paid or charged			(1,113)	(553)
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			1,236	4,026
Restructuring Charges, Total			1,400	10,720
Amounts paid or charged			(2,629)	(9,804)
Impact of currency exchange			0	(137)
Accrued restructuring, ending balance	$ 7	$ 4,805	$ 7	$ 4,805

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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