XML 24 R17.htm IDEA: XBRL DOCUMENT v3.19.3
Note 5 - Equity (Tables)
9 Months Ended
Sep. 30, 2019
Notes Tables  
Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block]
   
Number of
   
Weighted Avg.
 
   
Warrants
   
Exercise Price
 
Outstanding at January 1, 2018
   
748,060
    $
5.17
 
Issued
   
3,166,492
     
4.47
 
Cancelled or expired
   
(15,385
)    
 
Exercised
   
(34,615
)    
 
Outstanding at December 31, 2018
   
3,864,552
    $
4.60
 
Issued
   
     
 
Cancelled or expired
   
     
 
Exercised
   
     
 
Outstanding at September 30, 2019
   
3,864,552
    $
4.60
 
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]
Expected term:
10 years
Risk-free rate:
2.33% – 2.60%
Volatility:
76.87%
Dividend yield:
0%
Share-based Payment Arrangement, Option, Activity [Table Text Block]
   
Number of
   
Weighted Avg.
 
   
Shares
   
Exercise Price
 
Outstanding at January 1, 2018
   
2,628,749
    $
1.31
 
Options granted
   
2,034,525
     
6.21
 
Options exercised
   
     
 
Options expired
   
(127,593
)    
 
Outstanding at December 31, 2018
   
4,535,681
    $
3.31
 
Options granted
   
1,461,715
     
1.60
 
Options exercised
   
     
 
Options expired or cancelled
   
(91,813
)    
 
Outstanding at September 30, 2019
   
5,905,583
    $
2.94