Note 4 - Net Income Per Share (Tables)
 3 Months Ended
Jun. 30, 2015
Notes Tables  
Schedule of Weighted Average Number of Shares [Table Text Block]
 
 
Quarter Ended June 30
 
 
 
2015
 
 
2014
 
Weighted average common shares outstanding – basic
     4,854,841       4,851,043  
Effect of dilutive securities:
  
Stock options
     6,007       15,814  
Warrants
     -       602  
Shares used in computing net income per share – diluted
    4,860,848       4,867,459