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Note 9 - Stock-based Compensation (Details Textual) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		12 Months Ended
	Jan. 01, 2024	Dec. 31, 2023	Dec. 31, 2022	Jun. 30, 2020
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 14,400
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)		$ 3.69
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Intrinsic Value		$ 11	$ 6,300
The 2020 Stock Option and Incentive Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized				2,900
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant		5,100
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	10,200
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized	5,100
Restricted Stock [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 0
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)		0	0
Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount		$ 9,500
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition		2 years 7 months 6 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		4 years
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period		10 years
Restricted Stock Units (RSUs) [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount		$ 4,900
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)		900	0
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition		2 years 7 months 6 days