Note 6 - Restructuring (Details Textual) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Oct. 01, 2022	Sep. 30, 2023	Oct. 01, 2022
Restructuring Charges	$ 1,509	$ 2,315	$ 1,427	$ 2,505
Operating Lease, Impairment Loss			0	1,149
Q3 2023 Plan [Member]
Restructuring and Related Cost, Incurred Cost	1,500		1,500
Restructuring and Related Cost, Cost Incurred to Date	1,500		1,500
Q2 2019 Sales Plan [Member]
Restructuring and Related Cost, Cost Incurred to Date	3,100		3,100
Restructuring Charges	0	1,000	0	1,000
June 2017 Plan [Member]
Restructuring and Related Cost, Incurred Cost	100	1,300	100	$ 1,600
Restructuring and Related Cost, Cost Incurred to Date	$ 23,300		$ 23,300
June 2017 Plan [Member] | San Jose [Member]
Operating Lease, Impairment Loss		$ 1,100