XML 35 R25.htm IDEA: XBRL DOCUMENT v3.8.0.1
Note I - Stock-based Compensation (Tables)
 6 Months Ended
Oct. 31, 2017
Notes Tables  
Stock Option Plan Comparison [Table Text Block]
    Restated Option Plan
     
Minimum exercise price as a percentage of fair market value at date of grant    
100%
  
Last expiration date for outstanding options    
May 1, 2027
  
Shares available for grant at October 31, 2017    
284,000
  
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]
    Six Months Ended
October 31,
    2017   2016
Expected term (years)    
5.5
      
5.5
  
Risk-free interest rate    
1.81
 %    
1.28
 %
Volatility    
36
 %    
36
 %
Dividend yield    
-
      
-
  
Schedule of Share-based Compensation, Stock Options, Exercises [Table Text Block]
    Six Months Ended
October 31,
(Dollars in thousands)   2017   2016
Options exercised    
113,000
      
57,500
  
Cash received from option exercises   $
822
     $
860
  
Intrinsic value of options exercised   $
2,998
     $
1,335