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Note 4 - Restructuring Charges - Charges Related to the Wind Down Plan (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018
Restructuring Charges, Total	$ 814		$ 10,720
Integration Program [Member]
Accrued restructuring, beginning balance			4,026
Restructuring Charges, Total			10,720
Amounts paid or charged			(9,804)
Impact of currency exchange			(137)
Accrued restructuring, ending balance	4,805		4,805
Employee Severance [Member] \| Integration Program [Member]
Accrued restructuring, beginning balance			4,026
Restructuring Charges, Total			10,167
Amounts paid or charged			(9,251)
Impact of currency exchange			(137)
Accrued restructuring, ending balance	4,805		4,805
Other Restructuring [Member] \| Integration Program [Member]
Accrued restructuring, beginning balance
Restructuring Charges, Total			553
Amounts paid or charged			(553)
Impact of currency exchange
Accrued restructuring, ending balance