Note 5 - Securities Available-for-Sale (Details) - Amortized Cost and Estimated Fair Value of Securities (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2013
Dec. 31, 2014
Note 5 - Securities Available-for-Sale (Details) - Amortized Cost and Estimated Fair Value of Securities [Line Items]    
Amortized cost $ 33,311 $ 18,572
Unrealized Gain 4  
Unrealized Loss (5)  
Estimated Fair Value 33,310 18,572
Within One Year [Member]    
Note 5 - Securities Available-for-Sale (Details) - Amortized Cost and Estimated Fair Value of Securities [Line Items]    
Amortized cost 30,430 18,572
Unrealized Gain 2  
Unrealized Loss (4)  
Estimated Fair Value 30,428 18,572
After One Year [Member]    
Note 5 - Securities Available-for-Sale (Details) - Amortized Cost and Estimated Fair Value of Securities [Line Items]    
Amortized cost 2,881  
Unrealized Gain 2  
Unrealized Loss (1)  
Estimated Fair Value $ 2,882