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Note 9 - Stock-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions		12 Months Ended
	Jan. 01, 2026	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Jun. 30, 2020
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)		$ 2.69
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value		$ 36,614	$ 579	$ 11
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount		13,700
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 15,300
Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition		1 year 4 months 24 days
Restricted Stock Units (RSUs) [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition		1 year 2 months 12 days
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 1,600
The 2020 Stock Option and Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized					2.9
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant		5.3
The 2020 Stock Option and Incentive Plan [Member] \| Share-Based Payment Arrangement, Option [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period (Year)		4 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)		10 years
The 2020 Stock Option and Incentive Plan [Member] \| Subsequent Event [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant	12.4
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized	7.1