Note 3 - Revenue from Contracts with Customers (Tables)
 12 Months Ended
Feb. 29, 2020
Notes Tables  
Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block]
     
Twelve Months Ended
     
February 29 or 28:
     
2020
    
2019
Contract liabilities at the beginning of the year:
 $
          1,352,572
   $
          1,494,630
Revenue recognized
    
            (324,982)
    
            (335,028)
Contract fees received
    
             140,750
    
             205,500
Amortized gain on the financed sale of equipment
  
              (12,531)
    
              (12,530)
Contract liabilities at the end of the year:
 $
          1,155,809
   $
          1,352,572
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block]
2021
 
 $
195,658
  
2022
 
  
182,286
  
2023
 
  
168,450
  
2024
 
  
137,907
  
2025
 
  
124,620
  
Thereafter
 
  
346,888
  
Total
 
 $
1,155,809