Note 6 - Convertible Promissory Note - Convertible Promissory Note (Details) - Convertible Debt [Member] - The July 2019 Note [Member] - USD ($)	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Jul. 25, 2022	Dec. 31, 2021	Jul. 23, 2019
Maturity Date	Jul. 31, 2022	Jul. 31, 2022
Stated Interest Rate	24.00%			24.00%	24.00%
Conversion Price (in dollars per share)	$ 0.21		$ 0.21	$ 0.91	$ 1.80
Carrying Value	$ 1,000,000			$ 813,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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The price per share of the conversion feature embedded in the debt instrument.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

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