Note 3 - Fair Value Measurements (Details) - Estimated Fair Value of Warrants Accounted for as Liabilities (USD $)
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]    
Market value of stock at end of period (in Dollars per share) $ 1.90  
September 2010 Warrants [Member]    
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]    
Exercise price (in Dollars per share) $ 4.24 $ 4.24
Market value of stock at end of period (in Dollars per share) $ 1.90 $ 1.76
Expected dividend rate 0.00% 0.00%
Expected volatility 60.30% 77.40%
Risk-free interest rate 0.20% 0.30%
Expected life (in years) 284 days 1 year 284 days
May 2009 Warrants [Member]    
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]    
Exercise price (in Dollars per share)   $ 3.74
Market value of stock at end of period (in Dollars per share)   $ 1.76
Expected dividend rate   0.00%
Expected volatility   45.30%
Risk-free interest rate   0.10%
Expected life (in years)   146 days