Quarterly report pursuant to Section 13 or 15(d)

Note 6 - Employee and Director Benefits (Tables)

v3.10.0.1
Note 6 - Employee and Director Benefits (Tables)
 9 Months Ended
Sep. 30, 2018
Notes Tables  
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]
    2018   2017
Expected volatility    
24.72
 %    
29.00
 %
Expected dividends    
1.06
 %    
0.44
 %
Expected term (in years)    
6.25
      
6.25
  
Risk-free rate    
2.67
 %    
2.08
 %
Share-based Compensation, Stock Options, Activity [Table Text Block]
            Weighted    
   
 
  
Weighted
  
Average
  
 
   
 
  
Average
  
Remaining
  
Aggregate
   
 
  
Exercise
  
Contractual
  
Intrinsic
   
Shares
  
Price
  
Term (years)
  
Value
                             
(In Thousands)
  
Nine Months Ended September 30, 2018:                                
Outstanding at January 1, 2018    
1,666,834
 
   $
10.68
 
    
5.5
 
   $
51,377
 
Granted    
12,750
 
    
41.58
 
    
9.5
 
    
(31
)
Exercised    
(231,336
)
    
4.94
 
    
3.1
 
    
7,665
 
Forfeited    
(33,000
)
    
15.00
 
    
6.4
 
    
758
 
Outstanding at September 30, 2018    
1,415,248
 
    
11.79
 
    
5.1
 
   $
38,998
 
                                 
Exercisable at September 30, 2018    
693,100
 
   $
6.78
 
    
3.5
 
   $
22,513
 
                                 
Nine Months Ended September 30, 2017:                                
Outstanding at January 1, 2017    
2,026,334
 
   $
9.00
 
    
6.2
 
   $
57,636
 
Granted    
52,500
 
    
37.93
 
    
9.4
 
    
(35
)
Exercised    
(359,000
)
    
4.97
 
    
4.2
 
    
11,590
 
Forfeited    
(32,000
)
    
21.96
 
    
8.4
 
    
489
 
Outstanding at September 30, 2017    
1,687,834
 
    
10.51
 
    
5.7
 
   $
45,136
 
                                 
Exercisable at September 30, 2017    
810,736
 
   $
5.22
 
    
4.2
 
   $
25,971
 
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block]
    Shares   Weighted
Average Grant
Date Fair
Value
Nine Months Ended September 30, 2018:                
Non-vested at January 1, 2018    
120,676
     $
10.29
  
Granted    
12,850
      
41.48
  
Vested    
(73,700
 )    
5.88
  
Forfeited    
(750
 )    
41.21
  
Non-vested at September 30, 2018    
59,076
      
19.38
  
                 
Nine Months Ended September 30, 2017:                
Non-vested at January 1, 2017    
118,676
     $
8.88
  
Granted    
7,000
      
38.02
  
Vested    
(4,200
 )    
15.74
  
Forfeited    
(800
 )    
15.74
  
Non-vested at September 30, 2017    
120,676
      
10.29