Note 6 - Employee Benefit Plans - Reported Share-based Compensation in Consolidated Financial Statements (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 30, 2023	Dec. 31, 2022	Dec. 25, 2021
Share-based compensation of continuing operations	$ 17,237	$ 14,918	$ 13,792
Income tax benefit	(1,770)	(4,004)	(722)
Total share-based compensation, net of tax	15,467	10,914	13,070
Cost of Sales [Member]
Share-based compensation of continuing operations	845	646	828
Research and Development Expense [Member]
Share-based compensation of continuing operations	3,394	3,100	3,017
Selling, General and Administrative Expenses [Member]
Share-based compensation of continuing operations	$ 12,998	$ 11,172	$ 9,947

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479830/718-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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