Note 4 - Restructuring Charges - Charges Related to the Wind Down Plan (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 28, 2020	Mar. 30, 2019
Restructuring Charges, Total	$ 403	$ 1,361
Integration Program [Member]
Restructuring Charges, Total	2,000	1,400
Integration Program [Member] \| Employee Severance [Member]
Accrued restructuring, beginning balance	1,236	4,026
Restructuring Charges, Total	234	753
Amounts paid or charged	(1,218)	(1,029)
Impact of currency exchange	(33)	4
Accrued restructuring, ending balance	219	3,754
Integration Program [Member] \| Other Restructuring [Member]
Accrued restructuring, beginning balance
Restructuring Charges, Total	169	608
Amounts paid or charged	(169)	(608)
Impact of currency exchange
Accrued restructuring, ending balance
Integration Program [Member] \| Employee Severance and Other Exit Costs [Member]
Accrued restructuring, beginning balance	1,236	4,026
Restructuring Charges, Total	403	1,361
Amounts paid or charged	(1,387)	(1,637)
Impact of currency exchange	(33)	4
Accrued restructuring, ending balance	$ 219	$ 3,754

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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