XML 33 R26.htm IDEA: XBRL DOCUMENT v3.19.2
Note 4 - Accounts Receivable (Tables)
 6 Months Ended
Jun. 30, 2019
Notes Tables  
Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]
   
June 30, 2019
    
December 31,
2018
  
Accounts receivable
   $
1,715,033
     $
39,769
  
                 
Provision for doubtful accounts
    
(52,904
 )    
(27,666
 )
                 
Net accounts receivable
   $
1,662,129
     $
12,103