Note 5 - Property and Equipment - Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Jan. 02, 2021	Dec. 28, 2019
Property and Equipment	$ 150,848	$ 165,220
Accumulated depreciation and amortization	(111,182)	(125,990)
Property and Equipment, Net	39,666	39,230
Property, Plant and Equipment, Net	39,666	39,230
UNITED STATES
Property and Equipment, Net	29,440	32,313
Property, Plant and Equipment, Net	29,440	32,313
CHINA
Property and Equipment, Net	1,537	1,683
Property, Plant and Equipment, Net	1,537	1,683
PHILIPPINES
Property and Equipment, Net	2,912	2,683
Property, Plant and Equipment, Net	2,912	2,683
TAIWAN, PROVINCE OF CHINA
Property and Equipment, Net	5,171	1,885
Property, Plant and Equipment, Net	5,171	1,885
JAPAN
Property and Equipment, Net	476	283
Property, Plant and Equipment, Net	476	283
Other [Member]
Property and Equipment, Net	130	383
Property, Plant and Equipment, Net	130	383
Foreign Countries [Member]
Property and Equipment, Net	10,226	6,917
Property, Plant and Equipment, Net	10,226	6,917
Production Equipment and Software [Member]
Property and Equipment	135,774	150,591
Leasehold Improvements [Member]
Property and Equipment	12,913	12,517
Office Equipment [Member]
Property and Equipment	$ 2,161	$ 2,112

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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