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Note 6 - Convertible Promissory Note (Details Textual) - USD ($)	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Jan. 31, 2023	Dec. 31, 2022	Jul. 23, 2019
Amortization of Debt Discount (Premium)	$ 3,472,000	$ 213,000
The July 2019 Note [Member] \| Convertible Debt [Member]
Debt Instrument, Face Amount	$ 397,000			$ 1,000,000	$ 1,000,000
Debt Instrument, Interest Rate, Stated Percentage	24.00%			24.00%	24.00%
Debt Instrument, Convertible, Conversion Price	$ 2.65		$ 2.87	$ 6.30
Long-Term Debt, Fair Value	$ 1,239,000
Liabilities, Fair Value Adjustment	239,000
Carrying Value	397,000
Debt Instrument, Unamortized Discount	43,000
Amortization of Debt Discount (Premium)	174,000
Interest Expense, Debt	42,000	$ 60,000
The July 2019 Note [Member] \| Convertible Debt [Member] \| Conversion of July 2019 Note [Member]
Debt Conversion, Original Debt, Amount	$ 603,000
Debt Conversion, Converted Instrument, Shares Issued	215,000
Antidilutive Triggering Event [Member] \| Convertible Debt [Member]
Amortization of Debt Discount (Premium)	$ 41,000