Note 9 - Stockholders' Equity - Inputs Used in Valuation of Warrants (Details)	Jun. 30, 2017	Apr. 03, 2017
Measurement Input, Share Price [Member]
Inputs	6	9
Measurement Input, Exercise Price [Member]
Inputs	3.12	11.25
Measurement Input, Price Volatility [Member]
Inputs	0.5	0.5
Measurement Input, Expected Dividend Rate [Member]
Inputs	0	0
Measurement Input, Risk Free Interest Rate [Member] | Minimum [Member]
Inputs	0.0079	0.0079
Measurement Input, Risk Free Interest Rate [Member] | Maximum [Member]
Inputs	0.0188	0.0188
Measurement Input, Expected Term [Member] | Minimum [Member]
Inputs	0.08	0.24
Measurement Input, Expected Term [Member] | Maximum [Member]
Inputs	4.76	5