Note 3 - Earnings/(Loss) Per Share (Details Textual) - $ / shares	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Weighted Average Number of Shares Outstanding, Basic, Total	150,275,406	147,771,240	149,966,378	147,778,391
Common Stock, Shares, Outstanding, Ending Balance	150,409,472		150,409,472		148,542,805
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount			14,396,945	31,752,126
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	$ 0.22		$ 0.22
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	0.17		0.17
Class of Warrant or Right, Exercise Price of Warrants or Rights	0.25		0.25		$ 0.25
Debt Instrument, Convertible, Conversion Price	0.25		0.25
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price	0.34		0.34
Class of Warrant or Right, Exercise Price of Warrants or Rights	0.60		0.60		$ 0.60
Debt Instrument, Convertible, Conversion Price	$ 1.25		$ 1.25
Restricted Stock [Member]
Common Stock, Shares, Outstanding, Ending Balance	0	998,350	0	998,350

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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