Note 6 - Equity-based Compensation (Tables)
 3 Months Ended
Mar. 31, 2018
Notes Tables  
Share-based Compensation, Stock Options, Activity [Table Text Block]
   
For the Three Months Ended March 31, 2018
  
   
 
 
 
  
 
 
 
  
Average
  
   
 
 
 
  
Weighted-
    
Remaining
  
   
 
 
 
  
Average
    
Contractual
  
   
Shares
    
Exercise Price
    
Term (years)
  
                         
Outstanding, December 31, 2017
  
 
207,108
   
$
14.18
   
 
6.2
 
Granted
  
 
5,000
   
 
15.48
   
 
 
  
Exercised
  
 
-
   
 
-
    
 
 
  
Forfeited or expired
  
 
(1,002
)
  
 
14.90
   
 
 
  
                         
Outstanding, March 31, 2018
  
 
211,106
   
$
14.28
   
 
5.9
 
                         
Exercisable, March 31, 2018
  
 
28,456
   
$
9.65
   
 
1.3
 
   
For the Three Months Ended March 31, 2017
  
                   
Average
  
     
 
    
Weighted-
    
Remaining
  
     
 
    
Average
    
Contractual
  
   
Shares
    
Exercise Price
    
Term (years)
  
                         
Outstanding, December 31, 2016
    
34,190
     $
9.65
      
2.3
  
Granted
    
-
    
 
-
    
 
 
  
Exercised
    
-
    
 
-
    
 
 
  
Forfeited or expired
    
-
    
 
-
      
 
  
                         
Outstanding, March 31, 2017
    
34,190
     $
9.65
      
2.3
  
                         
Exercisable, March 31, 2017
    
34,190
     $
9.65
      
2.3
  
Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block]
Grant date stock price
  
$15.48
      
Dividend yield  
0.00%
      
Expected volatility  
19.55%
      
Risk-free interest rate  
2.75%
      
Expected life in years  
6