Note 11 - Stock-Based Compensation Plans - Share-based Payment Award Stock Options Valuation Assumptions (Details) - Employee Stock Purchase Plan [Member]	12 Months Ended
Dec. 31, 2022	Jan. 01, 2022	Jan. 02, 2021
Weighted average expected volatility	60.30%	39.90%	48.20%
Weighted average risk-free interest rate	3.74%	0.07%	0.89%
Expected term (in months) (Year)	6 years	6 years	6 years

The risk-free interest rate assumption that is used in valuing an option on its own shares.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iv)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

Rate of weighted-average expected volatility for award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(ii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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