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Note 2 - Summary of Significant Accounting Policies (Details Textual) $ in Thousands	1 Months Ended	12 Months Ended
	Aug. 31, 2020	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	May 31, 2018 USD ($)
Accounts Receivable, Allowance for Credit Loss, Recovery		$ 0	$ 198
Accounts Receivable, Credit Loss Expense (Reversal)		$ 27	0
Number of Operating Segments		3
Inventory Write-down		$ 703	544
Depreciation, Total		1,399	1,022
Deferred Grant Proceeds		368
Foreign Currency Transaction Gain (Loss), before Tax, Total		$ (203)	$ 9
Restricted Stock [Member] \| Vesting Based On Performance Metrics [Member] \| Restricted Stock Vesting in Three Years [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage	100.00%
Restricted Stock [Member] \| Employees [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period		4 years
Restricted Stock [Member] \| Independent Directors [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period		1 year
Restricted Stock [Member] \| Independent Directors [Member] \| Share-Based Payment Arrangement, Tranche One [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Rights, Percentage		25.00%
City of Rochester and State of New York [Member]
Contingent Liability, Repayment of State and Local Grant Funds Received				$ 550
Minimum [Member]
Property, Plant and Equipment, Useful Life		1 year
Maximum [Member]
Property, Plant and Equipment, Useful Life		10 years