Note 1 - Summary of Significant Accounting Policies - Reported Share-based Compensation in Consolidated Financial Statements (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 26, 2022	Mar. 27, 2021
Share-based compensation of continuing operations	$ 3,422	$ 3,523
Income tax benefit	(1,626)	(234)
Total share-based compensation, net	1,796	3,289
Cost of Sales [Member]
Share-based compensation of continuing operations	145	262
Research and Development Expense [Member]
Share-based compensation of continuing operations	752	781
Selling, General and Administrative Expenses [Member]
Share-based compensation of continuing operations	$ 2,525	$ 2,480

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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