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Note 5 - Stockholders' Equity (Details Textual)							9 Months Ended
Note 5 - Stockholders' Equity (Details Textual)	Sep. 25, 2020 USD ($) $ / shares shares	Aug. 12, 2020 $ / shares shares	Jul. 01, 2020 USD ($) $ / shares shares	Apr. 01, 2020 $ / shares shares	Feb. 14, 2019 USD ($) $ / shares shares	Oct. 05, 2018 $ / shares shares	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Aug. 21, 2018 USD ($) $ / shares shares
Warrants and Rights Outstanding, Reduction of Revenue During Period \| $							$ 26,958	$ 26,955
Shares Issued, Price Per Share (in dollars per share) \| $ / shares				$ 1.08
Proceeds from Issuance of Private Placement \| $							3,000,000
Proceeds from Issuance of Common Stock \| $							$ 7,257,925	$ 1,793,905
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)				1,444,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)				10 years
Performance Shares [Member] \| President and Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)				300,000
Performance Shares [Member] \| Chief Revenue Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)				150,000
Performance Shares [Member] \| Chief Financial Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)				200,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)				103,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period (Year)				3 years
Restricted Stock Units (RSUs) [Member] \| Director One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)				10,000
Restricted Stock Units (RSUs) [Member] \| Director Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)				30,000
Restricted Stock Units (RSUs) [Member] \| Director Three [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in shares)				30,000
Public Stock Offering [Member]
Sale of Stock, Number of Shares Issued in Transaction (in shares)					769,230
Sale of Stock, Price Per Share (in dollars per share) \| $ / shares					$ 2.60
Sale of Stock, Cash Fee, Percentage of Aggregate Gross Proceeds					6.00%
Sale of Stock, Consideration Received on Transaction \| $					$ 1,800,000
Shares Issued, Price Per Share (in dollars per share) \| $ / shares	$ 1.70
Stock Issued During Period, Shares, New Issues (in shares)	4,705,883
Cash Fee for Per Share of Common (in dollars per share) \| $ / shares	$ 0.12325
Proceeds from Issuance of Common Stock \| $	$ 7,400,000
Public Stock Offering [Member] \| Maximum [Member]
Payments of Stock Issuance Costs \| $	$ 100,000				$ 40,000
Private Placement [Member]
Shares Issued, Price Per Share (in dollars per share) \| $ / shares			$ 1.67
Stock Issued During Period, Shares, New Issues (in shares)			1,796,407
Proceeds from Issuance of Private Placement \| $			$ 3,000,000
Measurement Input, Risk Free Interest Rate [Member]
Warrants and Rights Outstanding, Measurement Input									0.0277
Measurement Input, Expected Term [Member]
Warrants and Rights Outstanding, Measurement Input									5
Measurement Input, Expected Dividend Rate [Member]
Warrants and Rights Outstanding, Measurement Input									0
Measurement Input, Price Volatility [Member]
Warrants and Rights Outstanding, Measurement Input									0.646
Common Stock Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)									150,000
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) \| $ / shares		$ 3.46
Warrants and Rights Outstanding \| $									$ 135,764
Stock Issued During Period, Shares, Warrants Exercised (in shares)		27,051
Class of Warrant or Right, Number of Warrants Exercised (in shares)		60,000
Common Stock Warrants, Tranche One [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)									30,000
Class of Warrant or Right, Vested During Period (in shares)						30,000
Class of Warrant or Right, Vested During Period, Exercise Price (in dollars per share) \| $ / shares						$ 1.80
Common Stock Warrants, Tranche One [Member] \| Measurement Input, Share Price [Member]
Warrants and Rights Outstanding, Measurement Input									0.94
Common Stock Warrants, Tranche Two [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)									120,000
Warrants and Rights Outstanding, Term (Year)									4 years
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) \| $ / shares									$ 2
Class of Warrant or Right, Exercise Price of Warrants or Rights, Maximum Percentage of Market Price of Common Stock									120.00%
Common Stock Warrants, Tranche Two [Member] \| Measurement Input, Share Price [Member]
Warrants and Rights Outstanding, Measurement Input									0.9