Note 9 - Stockholders' Equity (Details Textual) - USD ($) | 1 Months Ended | 3 Months Ended | | |
Mar. 31, 2018 | Mar. 31, 2018 | Mar. 31, 2017 | Feb. 28, 2018 | Dec. 31, 2017 |
Conversion of Stock, Shares Converted | | 450 | | | |
Conversion of Stock, Shares Issued | | 30,000,000 | | | |
Preferred Stock, Par or Stated Value Per Share | $ 0.01 | $ 0.01 | | | $ 0.01 |
Stock Issued During Period, Shares, Issued for Services | | 5,000,000 | | | |
Warrants and Rights Outstanding, Term | | | | 5 years | |
Class of Warrant or Right, Number of Securities Called by Warrants or Rights | | | | 178,571 | |
Common Stock, Par or Stated Value Per Share | $ 0.001 | $ 0.001 | | $ 0.042 | $ 0.001 |
Class of Warrant or Right, Outstanding | 0 | 0 | | | |
Employee Stock Option [Member] | | | | | |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Total | $ 194,302 | $ 194,302 | | | |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition | | 2 years 146 days | | | |
Common Stock Issued For Services [Member] | | | | | |
Allocated Share-based Compensation Expense, Total | | $ 28,571 | | | |
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Total | $ 171,429 | 171,429 | | | |
2006 Equity Incentive Plan [Member] | | | | | |
Allocated Share-based Compensation Expense, Total | | $ 23,978 | $ 14,580 | | |
Conversion of Series D Preferred Stock Into Common Stock [Member] | | | | | |
Conversion of Stock, Shares Converted | | 450 | | | |
Stock Issued During Period, Shares, New Issues | | 30,000,000 | | | |
Series B Convertible Preferred Stock [Member] | | | | | |
Preferred Stock, Shares Outstanding, Ending Balance | 100 | 100 | | | 100 |
Convertible Preferred Stock, Conversion Price1 | $ 0.35 | $ 0.35 | | | |
Convertible Preferred Stock, Total Conversion Shares | 285,714 | 285,714 | | | |
Conversion of Stock, Shares Converted | | 0 | | | |
Preferred Stock, Par or Stated Value Per Share | $ 1,000 | $ 1,000 | | | $ 1,000 |
Series C Convertible Preferred Stock [Member] | | | | | |
Preferred Stock, Shares Outstanding, Ending Balance | 2,570 | 2,570 | | | 2,570 |
Convertible Preferred Stock, Conversion Price1 | $ 0.015 | $ 0.015 | | | |
Convertible Preferred Stock, Total Conversion Shares | 171,349,733 | 171,349,733 | | | |
Conversion of Stock, Shares Converted | | 0 | | | |
Preferred Stock, Par or Stated Value Per Share | $ 1,000 | $ 1,000 | | | $ 1,000 |
Series D Convertible Preferred Stock [Member] | | | | | |
Preferred Stock, Shares Outstanding, Ending Balance | 550 | 550 | | | 1,000 |
Convertible Preferred Stock, Conversion Price1 | $ 0.015 | $ 0.015 | | | |
Convertible Preferred Stock, Total Conversion Shares | 36,666,666 | 36,666,666 | | | |
Conversion of Stock, Shares Converted | | 450 | | | |
Conversion of Stock, Shares Issued | | 30,000,000 | | | |
Preferred Stock, Par or Stated Value Per Share | $ 1,000 | $ 1,000 | | | $ 1,000 |
Series E Convertible Preferred Stock [Member] | | | | | |
Preferred Stock, Shares Outstanding, Ending Balance | 600 | 600 | | | 0 |
Convertible Preferred Stock, Conversion Price1 | $ 0.08 | $ 0.08 | | | |
Conversion of Stock, Shares Converted | 600 | | | | |
Preferred Stock, Par or Stated Value Per Share | $ 1,000 | $ 1,000 | | | $ 1,000 |
Proceeds From Issuance Of Convertible Preferred Stock, Net of Issuance Cost | $ 590,000 | | | | |