Quarterly report pursuant to Section 13 or 15(d)

Note 10 - Shareholders' Equity (Details Textual)

v3.20.2
Note 10 - Shareholders' Equity (Details Textual) - USD ($)
 6 Months Ended
Aug. 10, 2020
Feb. 13, 2020
Jun. 30, 2020
Jun. 30, 2019
Mar. 31, 2020
Stock Issued During Period, Shares, New Issues (in shares)   2,125,000      
Shares Issued, Price Per Share (in dollars per share) $ 5       $ 4
Proceeds from Issuance of Common Stock $ 23,000,000 $ 8,500,000 $ 7,682,000  
Proceeds from Issuance of Common Stock, Net $ 21,100,000 $ 7,700,000      
Stock Issued During Period, Value, Stock Options Exercised     $ 16,000 $ 75,000  
Warrants Issued in Private Placement [Member]          
Stock Issued During Period, Shares, Exercise of Common Stock Warrants (in shares)     0 0  
Private Placement [Member]          
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period (in shares)     7,200 50,000  
Stock Issued During Period, Value, Stock Options Exercised     $ 16,000 $ 75,000