Note 9 - Convertible Notes - Convertible Notes (Details) (Parentheticals)	6 Months Ended	12 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Convertible Notes 1[Member]
Interest Rate	7.00%	7.00%
Conversion Rights	335,833	335,833
Convertible Notes 2 [Member]
Interest Rate	5.00%	5.00%
Conversion Rights	3,013,190	3,013,190
Maturing Dates Range Start	May 01, 2018	May 01, 2018
Maturing Dates Range End	May 31, 2021	May 31, 2021

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 CCYY-MM-DD format.

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

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