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Note 14 - Stock Based Compensation (Details Textual) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended
	May 14, 2021	Mar. 31, 2022	Mar. 31, 2021	Mar. 24, 2020
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)		2,722
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period (in shares)
Share-Based Payment Arrangement, Expense		$ 1,806	$ 640
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Nonvested, Number of Shares, Ending Balance (in shares)		5,470
Defined Contribution Plan, Employer Matching Contribution, Percent of Match		6.00%
Defined Contribution Plan, Cost		$ 34	$ 33
Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount		$ 8,279
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)		1 year 5 months 23 days
The 2020 Stock Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)				3,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized (in shares)	15,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross (in shares)		2,722	0
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in dollars per share)		$ 1.07
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period (in shares)		0	0
The 2020 Stock Incentive Plan [Member] \| Share-Based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in shares)		9,214
Share-Based Payment Arrangement, Expense		$ 1,806	$ 640