Note 5 - Financial Instruments Measured at Fair Value - Short-term Investments by Security Type (Details) - USD ($) $ in Thousands		Mar. 28, 2020	Dec. 28, 2019
Estimated Fair Value		$ 901	$ 904	[1]
Debt Security, Government, Non-US [Member]
Amortized Cost		901	904
Gross Unrealized Gains
Gross Unrealized Losses	[2]
Estimated Fair Value		$ 901	$ 904

[1] Derived from December 28, 2019 audited financial statements

[2] As of December 28, 2019 and December 29, 2018 we had no investments with loss positions.