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Note 8 - Stock-based Compensation (Details Textual) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions		9 Months Ended
	Jan. 01, 2023	Sep. 30, 2023	Sep. 30, 2022	Jun. 30, 2020
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 15,800
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)		$ 2.82	$ 2.30
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value		$ 34	$ 19
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount		$ 10,400
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 Additional Shares Authorized	5.1
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant		5.1
Restricted Stock [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 100
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition		3 months 18 days
Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition		2 years 9 months 18 days
Share-Based Payment Arrangement, Option [Member] \| The 2020 Stock Option and Incentive Plan [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
Restricted Stock Units (RSUs) [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 5,400
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition		2 years 9 months 18 days