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Note 4 - Restructuring Charges - Charges Related to the Wind Down Plan (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Restructuring Charges, Total	$ 8,545		$ 9,906
Integration Program [Member]
Accrued restructuring, beginning balance			4,026
Restructuring Charges, Total			9,906
Amounts paid or charged			(5,784)
Impact of currency exchange			26
Accrued restructuring, ending balance	8,174		8,174
Employee Severance [Member] \| Integration Program [Member]
Accrued restructuring, beginning balance			4,026
Restructuring Charges, Total			9,412
Amounts paid or charged			(5,290)
Impact of currency exchange			26
Accrued restructuring, ending balance	8,174		8,174
Other Restructuring [Member] \| Integration Program [Member]
Accrued restructuring, beginning balance
Restructuring Charges, Total			494
Amounts paid or charged			(494)
Impact of currency exchange
Accrued restructuring, ending balance