Note 12 - Federal Income Taxes (Tables)
 12 Months Ended
Dec. 31, 2016
Notes Tables  
Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]
 
 
2016
 
 
2015
 
 
2014
 
Current
 
$
2,725
 
   $
(660
 )   $
69
 
Deferred
 
 
3,512
 
    
5,680
     
2,503
 
Tax expense (benefit)
 
$
6,237
 
   $
5,020
    $
2,572
 
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]
 
 
2016
 
 
2015
 
 
2014
 
Statutory rate
 
 
34.0
%
    
34.0
%
    
34.0
 
Municipal interest income
 
 
(2.0
)
    
(2.1
 )    
(3.9
 )
Other, net
 
 
(1.9
)
    
(2.5
 )    
(4.1
 )
Valuation allowance
 
 
-
 
    
-
     
-
 
Effective tax rate
 
 
30.1
%
    
29.4
%
    
26.0
 
Schedule of Deferred Tax Assets and Liabilities [Table Text Block]
 
 
2016
 
 
2015
 
Deferred federal income tax assets:
                
Allowance for loan losses
 
$
2,990
 
   $
3,818
 
Net deferred loan origination fees
 
 
655
 
    
649
 
Tax versus book depreciation differences
 
 
331
 
    
482
 
Net unrealized losses on securities available for sale
 
 
3,449
 
    
795
 
Accrued postretirement benefits
 
 
3,406
 
    
3,176
 
Postretirement benefits in other comprehensive income
 
 
427
 
    
417
 
Alternative minimum tax
 
 
3,493
 
    
632
 
Non-accrual loan interest
 
 
281
 
    
438
 
Other real estate owned
 
 
546
 
    
606
 
Net operating loss
 
 
-
 
    
5,425
 
Other, net
 
 
766
 
    
783
 
Total deferred federal tax asset
 
$
16,344
 
   $
17,221
 
                 
Deferred federal income tax liabilities:
                
Accretion of bond discount
 
$
(186
)
   $
(346
 )
Other
 
 
(691
)
    
(560
 )
Total deferred federal tax liabilities
 
$
(877
)
   $
(906
 )
Net deferred federal income tax asset
 
$
15,467
 
   $
16,315