Note 15 - Income Taxes - Unrecognized Tax Benefits (Details) $ in Thousands	12 Months Ended
Dec. 28, 2019 USD ($)
Balance as of December 29, 2018	$ 628
Charges for current year tax positions	(628)
Reserves for current year tax position
Balance as of December 28, 2019

Amount of unrecognized tax benefits.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
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Amount of decrease in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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