Note 9 - Stockholders Equity (Details Textual) - USD ($)							1 Months Ended	6 Months Ended	12 Months Ended
	Jun. 21, 2017	Dec. 21, 2016	Dec. 05, 2016	Dec. 05, 2016	Dec. 02, 2016	Nov. 30, 2012	Jun. 30, 2016	Jun. 30, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Common Stock, Par or Stated Value Per Share									$ 0.005	$ 0.005
Payments of Stock Issuance Costs									$ 758,796
Proceeds from Issuance of Common Stock									$ 5,175,000
Share Based Compensation Warrants Outstanding									180,001	150,001	250,001
Stock Issued from Exercise of Warrants										100,000
Class of Warrant or Right, Issued During Period, Exercise Price							$ 0.70
Class of Warrant or Right, Grants in Period, Grant-date Fair Value							$ 0.36
Class of Warrants or Rights, Vesting Period							1 year
Class of Warrants or Rights, Vested During the Period		15,000
Warrant Expense									$ 5,300
Proceeds from Warrant Exercises										$ 77,100
Aggregate Intrinsic Value Of Warrants Exercised										$ 102,000
Class of Warrant or Right, Issued During Period										0
Scenario, Forecast [Member]
Class of Warrants or Rights, Vested During the Period	15,000
Monthly Warrant Expense								$ 5,300
Warrant [Member]
Share Based Compensation Warrants Outstanding									150,001
Stock Issued from Exercise of Warrants							30,000
Investors [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights						$ 0.55
Warrants Expiration Period						5 years
Option Plan 2010 Member | Consultant [Member]
Stock Issued During Period, Shares, Issued for Services									3,031	15,971
Allocated Share-based Compensation Expense									$ 1,714	$ 10,380
Secondary Stock Offering [Member]
Stock Issued During Period, Shares, New Issues					11,250,000
Common Stock, Par or Stated Value Per Share					$ 0.005
Shares Issued, Price Per Share					$ 0.40
Proceeds from Issuance of Common Stock, Gross			$ 5,175,000
Payments of Stock Issuance Costs			758,795
Proceeds from Issuance of Common Stock			$ 4,416,204
Over-Allotment Option [Member]
Stock Issued During Period, Shares, New Issues				1,687,500
Underwriter Option, Term					30 days