Note 7 - Convertible Notes - Convertible Notes (Details) (Parentheticals) - Convertible Debt [Member]	3 Months Ended	12 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Conversion Rights		914,732
Convertible Notes 1[Member]
Interest Rate	5.00%	5.00%
Conversion Rights	363,767	363,767
Maturity Date, start	May 01, 2018	May 01, 2018
Maturity Date, end	Oct. 31, 2021	Oct. 31, 2021
Convertible Notes 2 [Member]
Interest Rate	5.00%	5.00%
Conversion Rights	550,965	550,965
Maturity Date, start	Jun. 01, 2022	Jun. 01, 2022
Maturity Date, end	Dec. 31, 2022	Dec. 31, 2022

The number of equity instruments that the holder of the debt instrument would receive if the debt was converted to equity.

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

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Latest date the outstanding debt instruments are required to be repaid, in YYYY-MM-DD format.

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Earliest date the outstanding debt instruments are required to be repaid, in YYYY-MM-DD format.

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