Note 8 - Mortgage Servicing Rights ("MSR"s) (Tables)
 12 Months Ended
Dec. 31, 2016
Notes Tables  
Mortgage Servicing Rights [Table Text Block]
(dollars in thousands)
 
2016
 
 
2015
 
 
2014
 
Balance, January 1
  $
5,142
     $
4,765
     $
4,750
  
Additions
   
1,321
      
1,037
      
547
  
Amortization
   
(750
)
    
(590
)
    
(476
)
Impairment
   
(131
)
    
(70
)
    
(56
)
Balance, December 31
  $
5,582
     $
5,142
     $
4,765
  
Fair value
  $
6,154
     $
5,726
     $
5,456
  
Residential mortgage loans serviced for others
   $
631,889
     $
601,939
     $
590,660
  
Schedule of Valuation Allowance for Impairment of Recognized Servicing Assets [Table Text Block]
(dollars in thousands)
 
2016
 
 
2015
 
 
2014
 
Balance, January 1
  $
(1,674
)
   $
(1,604
)
   $
(1,548
)
Impairment
   
(715
)
    
(123
)
    
(97
)
Recovery
   
584
      
53
      
41
  
Balance, December 31
  $
(1,805
)
   $
(1,674
)
   $
(1,604
)
Fair Value of Mortgage Servicing Rights [Table Text Block]
(dollars in thousands)
 
 
 
 
Fair value amount of MSRs
  $
6,154
  
Weighted average life (in years)
   
6.3
  
Prepayment speeds (constant prepayment rate)*
    
10.2
%
Impact on fair value:
        
10% adverse change
  $
(115
)
20% adverse change
  $
(238
)
Discount rate
   
9.55
%
Impact on fair value:
       
10% adverse change
  $
(225
)
20% adverse change
  $
(434
)