Note 2 - Summary of Significant Accounting Policies (Details Textual) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Accounts Receivable, Credit Loss Expense (Reversal)	$ 0	$ 0
Number of Operating Segments	2
Number of Reportable Segments	2
Inventory Write-down	$ 203	444
Depreciation, Total	666	630
Deferred Grant Proceeds	73
Foreign Currency Transaction Gain (Loss), before Tax, Total	(34)	$ (26)
City of Rochester and State of New York [Member]
Contingent Liability, Repayment of State and Local Grant Funds Received	463
Covenant, Future Amount Receivable	370
Interest Rate Swap [Member]
Derivative Liability, Total	$ 21
Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	1 year
Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	10 years