Note 5 - Stock Warrant Activity (Details)	6 Months Ended
	Jun. 30, 2016 $ / shares shares
Weighted Average [Member]
Outstanding, warrants price range (in dollars per share) | $ / shares
Granted, warrants price range (in dollars per share) | $ / shares
Cancelled/Expired, warrants price range (in dollars per share) | $ / shares
Exercised, warrants price range (in dollars per share) | $ / shares
Outstanding, warrants price range (in dollars per share) | $ / shares
Exercisable, warrants price range (in dollars per share) | $ / shares
Outstanding, warrants (in shares) | shares
Granted, warrants (in shares) | shares
Cancelled/Expired, warrants (in shares) | shares
Exercised, warrants (in shares) | shares
Outstanding, warrants (in shares) | shares
Exercisable, warrants (in shares) | shares