Note 7 - Leases (Details Textual) - USD ($) $ in Thousands	3 Months Ended
	Apr. 03, 2021	Mar. 28, 2020	Jan. 02, 2021
Operating Lease, Right-of-Use Asset	$ 28,006		$ 22,178
Operating Lease, Weighted Average Remaining Lease Term (Year)	4 years 9 months 18 days
Operating Lease, Weighted Average Discount Rate, Percent	5.30%
Operating Lease, Cost	$ 2,000	$ 1,900
Operating Lease Liability for Previously Restructured Facilities	8,000
Operating Lease, Liability, Total	29,123		$ 23,055
Hillsboro, Oregon and Shanghai, China Facility Leases [Member]
Operating Lease, Right-of-Use Asset	7,200
Operating Lease, Liability, Total	$ 7,200