Note 10 - Stock-Based Compensation Plans - Stock-based Compensation (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 02, 2021	Dec. 28, 2019	Dec. 31, 2018
Total stock-based compensation	$ 40,372	$ 18,899	$ 13,646
Cost of Sales [Member]
Total stock-based compensation	3,179	1,422	940
Research and Development Expense [Member]
Total stock-based compensation	10,124	5,640	4,357
Selling, General and Administrative Expenses [Member]
Total stock-based compensation	$ 27,069	$ 11,837	$ 8,349

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

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