Note 1 - Summary of Significant Accounting Policies - Reported Share-based Compensation in Consolidated Financial Statements (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 25, 2022	Jun. 26, 2021	Jun. 25, 2022	Jun. 26, 2021
Share-based compensation of continuing operations	$ 3,933	$ 3,506	$ 7,355	$ 7,029
Income tax benefit	(836)	(180)	(2,462)	(414)
Total share-based compensation, net	3,097	3,326	4,893	6,615
Cost of Sales [Member]
Share-based compensation of continuing operations	172	191	317	453
Research and Development Expense [Member]
Share-based compensation of continuing operations	826	763	1,578	1,544
Selling, General and Administrative Expenses [Member]
Share-based compensation of continuing operations	$ 2,935	$ 2,552	$ 5,460	$ 5,032

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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

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