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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Note 5 - Share-based Compensation (Details Textual) - USD ($)									3 Months Ended		9 Months Ended
	Jun. 29, 2018	Jun. 22, 2018	Sep. 07, 2017	Sep. 05, 2017	Jun. 19, 2017	May 02, 2017	Apr. 30, 2017	Feb. 10, 2017	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2017	Feb. 08, 2018	Dec. 18, 2017
Share Price													$ 0.3147	$ 0.41
President and Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period						10 years
Employment Agreement, Option, Number of Shares, Expected to Grant						3,731,322
Employment Agreement, Term						5 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period						5 years
Employment Agreement, Lock-up Agreement, Successful Commercialization, Minimum Cash Receipt						$ 3,000,000
Employment Agreement, Lock-up Agreement, Minimum Revenue Recognized						$ 3,000,000
Non-Qualified Stock Option [Member] \| President and Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period						10 years
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price						$ 0.45
Sharebased Compensation Arrangement by Sharebased Payment Award Options Granted in Period, Fair Value						$ 1,679,095
2007 Stock Option [Member] \| President and Chief Executive Officer [Member]
Stock Issued During Period, Shares, New Issues							3,866,630
Investment Options, Exercise Price							$ 0.18
Share Price							$ 0.51
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period							3,866,629
Shares Issued for the Exercise of 2007 Stock Option [Member] \| President and Chief Executive Officer [Member]
Stock Issued During Period, Shares, New Issues							2,501,937
2018 Equity Incentive Plan [Member]
Allocated Share-based Compensation Expense, Total										$ 136,150
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period		10 years
Common Stock, Capital Shares Reserved for Future Issuance		40,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant, Increase Each Year, Maximum Percentage	5.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	296,976								790,087	493,111
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 0.43								$ 0.34
2018 Equity Incentive Plan [Member] \| Minimum [Member]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price										$ 0.25
2018 Equity Incentive Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price									$ 0.43	$ 0.31
The 2007 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross												340,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price												$ 0.65
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period											110,000
The 2007 Equity Incentive Plan [Member] \| Non-employee Members of the Board of Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross					40,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price					$ 0.43
The 2007 Equity Incentive Plan [Member] \| Chief Financial Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross								300,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price								$ 0.69
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares								125,000
Sharebased Compensation Arrangement by Sharebased Payment Award Options Granted in Period, Fair Value								$ 207,000
The 2007 Equity Incentive Plan [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period			10 years
Outside of the 2007 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross											1,211,527	6,828,872
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price											$ 0.26	$ 0.46
Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period											2,400,000	3,866,629
Outside of the 2007 Plan [Member] \| Board of Directors and Vendors [Member]
Allocated Share-based Compensation Expense, Total											$ 315,551	$ 389,976
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross											1,211,527	1,097,550
Outside of the 2007 Plan [Member] \| Non-Qualified Stock Option [Member] \| Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period				10 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				2,000,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price				$ 0.45
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period				5 years
Outside of the 2007 Plan [Member] \| Minimum [Member] \| Board of Directors and Vendors [Member]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price												$ 0.43
Outside of the 2007 Plan [Member] \| Minimum [Member] \| Board Of Directors [Member]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price											$ 0.23
Outside of the 2007 Plan [Member] \| Maximum [Member] \| Board of Directors and Vendors [Member]
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price											$ 0.43	$ 0.67
Selling, General and Administrative Expenses [Member]
Allocated Share-based Compensation Expense, Total											$ 984,157	$ 801,716
Selling, General and Administrative Expenses [Member] \| Non-Qualified Stock Option [Member] \| President and Chief Executive Officer [Member]
Allocated Share-based Compensation Expense, Total											$ 251,865	$ 111,940
Selling, General and Administrative Expenses [Member] \| 2018 Equity Incentive Plan [Member] \| Employee Stock Option [Member]
Allocated Share-based Compensation Expense, Total	$ 127,700
Selling, General and Administrative Expenses [Member] \| The 2007 Equity Incentive Plan [Member] \| Non-employee Members of the Board of Directors [Member]
Allocated Share-based Compensation Expense, Total					$ 15,600