Note 6 - Net Income Per Share (Tables)
 9 Months Ended
Jan. 31, 2014
Earnings Per Share [Abstract]  
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]
   
Three Months Ended
January 31,
   
Nine Months Ended
January 31,
 
   
2014
   
2013
   
2014
   
2013
 
Numerator:
                       
Net income
  $ 569     $ 716     $ 1,486     $ 968  
                                 
Denominator:
                               
Weighted average common shares
  Outstanding – basic
    3,814       3,914       3,856       3,895  
     Effect of dilutive options outstanding
    139       11       91       9  
Weighted average common shares
  outstanding – diluted
    3,953       3,925       3,947       3,904