Note 2 - Acquisitions and Dispositions (Tables)
 12 Months Ended
Mar. 31, 2017
Notes Tables  
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]
Cash consideration
   $
8,747
  
Holdback payment liability
    
637
  
Contingent consideration liability
    
9,271
  
Aggregate consideration
   $
18,655
  
         
Accounts receivable
   $
925
 
Inventories
    
310
  
Property, plant and equipment
    
530
  
Intangibles
    
5,869
  
Goodwill
    
13,833
  
Accounts payable
    
(470
 )
Accrued liabilities
    
(767
 )
Deferred income taxes
    
(1,575
 )
Total purchase price allocation
   $
18,655
  
Cash consideration
   $
10,322
  
Holdback payment liability
    
1,000
  
Aggregate consideration
   $
11,322
  
         
Cash
   $
20
 
Accounts receivable
    
285
  
Inventories
    
85
  
Property, plant and equipment
    
229
  
Intangibles
    
4,454
  
Goodwill
    
7,962
  
Accrued liabilities
    
(100
 )
Unearned revenues
    
(1,613
 )
Total purchase price allocation
   $
11,322
  
Cash consideration
   $
5,000
  
Holdback payment liability
    
250
  
Contingent consideration liability
    
300
  
Aggregate consideration
   $
5,550
  
         
Inventories
   $
137
 
Property, plant and equipment
    
7
  
Intangibles
    
3,678
  
Goodwill
    
1,743
  
Accrued expenses
    
(15
)
Total purchase price allocation
   $
5,550
  
Inventories
   $
1,268
  
Property, plant and equipment
    
47
  
Intangibles
    
5,711
  
Goodwill
    
3,295
  
Accrued expenses
    
(53
 )
Total purchase price allocation
   $
10,268
  
Business Acquisition, Pro Forma Information [Table Text Block]
 
 
Year
Ended
March
31,
 
 
 
201
6
 
 
201
5
 
Revenues
   $
86,499
     $
74,379
  
Net income
    
11,471
      
9,944
  
Net Income per common share:
                
Basic
   $
3.18
     $
2.82
  
Diluted
    
3.05
      
2.72
  
 
 
Year
Ended
March
31,
 
 
 
201
6
 
 
201
5
 
Revenues
   $
86,053
     $
75,649
  
Net income
    
11,463
      
10,182
  
Net Income per common share:
                
Basic
   $
3.18
     $
2.89
  
Diluted
    
3.05
      
2.79
  
 
 
Year E
nded March 31,
 
 
 
2015
 
 
2014
 
Revenues
   $
73,068
     $
56,541
  
Net income
    
9,673
      
9,512
  
Net income per common share:
                
Basic
   $
2.75
    $
2.76
 
Diluted
    
2.65
      
2.63
  
 
 
Year E
nded March 31,
 
 
 
2015
 
 
2014
 
Revenues
   $
71,648
     $
60,388
  
Net income
    
9,661
      
11,141
  
Net income per common share:
                
Basic
   $
2.74
    $
3.23
 
Diluted
    
2.65
      
3.09