Note 10 - Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Jan. 01, 2023	Jan. 02, 2022	Jan. 01, 2018	Dec. 31, 2017
Deferred Tax Assets, Valuation Allowance	$ 56,783	$ 56,862
Deferred Tax Liability Not Recognized, Amount of Unrecognized Deferred Tax Liability, Undistributed Earnings of Foreign Subsidiaries		100	$ 100
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	2,500	$ 0
Federal [Member]
Operating Loss Carryforwards	169,500			$ 63,200	$ 106,300
State and Local Jurisdiction [Member]
Operating Loss Carryforwards	94,200
Research Tax Credit Carryforward [Member]
Tax Credit Carryforward, Capitalized	8,500
Research Tax Credit Carryforward [Member] | Federal [Member]
Tax Credit Carryforward, Amount	4,600
Research Tax Credit Carryforward [Member] | State and Local Jurisdiction [Member]
Tax Credit Carryforward, Amount	$ 5,500