Note 10 - Commitments and Contingencies (Details Textual)			12 Months Ended
	Dec. 31, 2017 USD ($) $ / shares shares	Jun. 23, 2009 USD ($)	Dec. 31, 2017 USD ($) $ / shares shares	Dec. 31, 2016 USD ($)
Operating Leases, Rent Expense			$ 1,125,147	$ 1,071,363
Loss Contingency, Pending Claims, Number	6,496,827		6,496,827
Proceeds from Warrant Exercises			$ 155,000	0
License Payments		$ 300,000
Additional Income (Expense) Related to Settlement Agreement			$ 108,702	$ (94,129)
Settlement and Licensing Agreement [Member]
Patent Royalty Percentage Obligation			2.00%
Class of Warrant or Right, Number of Securities Called by Warrants or Rights | shares	1,000,000		1,000,000
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares	$ 0.01		$ 0.01
Loss Contingency, Estimate of Possible Loss	$ 300,000		$ 300,000
Class of Warrant or Right, Percentage, Exercised for Stock	50.00%
Stock Issued During Period, Shares, Exercise of Warrants | shares	500,000
Class of Warrant or Right, Percentage, Exercised for Cash Payment	50.00%
Proceeds from Warrant Exercises	$ 145,000