Note 3 - Inventories (Tables)
 12 Months Ended
Mar. 31, 2017
Notes Tables  
Schedule of Inventory, Current [Table Text Block]
 
 
March 31,
 
 
 
201
7
 
 
201
6
 
Raw materials
   $
10,815
    $
9,433
  
Work-in-process
    
342
      
337
  
Finished goods
    
3,604
      
4,941
  
Less reserve
    
(888
 )    
(694
 )
    $
13,873
     $
14,017