Note 10 - Derivative Financial Instruments and Hedging Transactions (Tables)
 12 Months Ended
Dec. 31, 2016
Notes Tables  
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block]
   
Balance Sheet
          
Notional
  
December 31, 2016
  
Location
  
Fair Value
    
Amount
  
Interest rate swaps designated as fair value hedges
  
Other Liabilities
   $
(276
 )    
15,847
 
Interest rate swaps with customers
  
Other Assets
   $
91
     
26,624
 
Reciprocal interest rate swaps
  
Other Liabilities
   $
(91
 )    
26,624
 
Forward commitment to sell mortgage-backed securities
  
Other Assets
   $
90
     
15,000
 
Schedule of Derivative Instruments [Table Text Block]
   
Balance Sheet
          
Notional
  
December 31, 2015
  
Location
  
Fair Value
    
Amount
  
Interest rate swaps designated as fair value hedges
  
Other Liabilities
   $
(443
 )    
17,516
 
Interest rate swaps with customers
  
Other Assets
   $
75
     
7,648
 
Reciprocal interest rate swaps
  
Other Liabilities
   $
(75
 )    
7,648