Quarterly report pursuant to Section 13 or 15(d)

Note 10 - Preferred Stock (Details Textual)

v3.21.2
Note 10 - Preferred Stock (Details Textual)
3 Months Ended 9 Months Ended 22 Months Ended
Jan. 19, 2021
shares
Nov. 26, 2019
Nov. 12, 2019
shares
Sep. 30, 2021
USD ($)
$ / shares
shares
Sep. 30, 2021
USD ($)
$ / shares
shares
Sep. 30, 2021
USD ($)
$ / shares
shares
Mar. 31, 2021
shares
Dec. 31, 2020
shares
Dec. 16, 2020
shares
Dec. 15, 2020
shares
Sep. 30, 2020
shares
Preferred Stock, Shares Authorized (in shares)       10,000,000 10,000,000 10,000,000   10,000,000 [1]      
Warrants Issued Upon Conversion of Term Loan with CRG [Member]                      
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)     989,379                
Conversion of Term Loan with CRG Into Series B Convertible Preferred Stock [Member]                      
Debt Conversion, Converted Instrument, Shares Issued (in shares)     31,300                
Series A Preferred Stock [Member]                      
Preferred Stock, Shares Outstanding, Ending Balance (in shares)       0 0 0     0    
Preferred Stock, Shares Authorized (in shares)                   547,345  
Convertible Preferred Stock, Shares Issued upon Conversion (in shares)       1 1 1          
Series B Preferred Stock [Member]                      
Preferred Stock, Shares Outstanding, Ending Balance (in shares)       39,279 39,279 39,279   35,819 [1]     34,735
Preferred Stock, Dividend Rate, Percentage   12.50%                  
Preferred Stock Dividends, Shares (in shares)       1,189 3,460 7,979          
Dividends, Preferred Stock, Cash | $       $ 1,000 $ 4,000 $ 14,000          
Convertible Preferred Stock, Shares Issued upon Conversion (in shares)       2,567,255 2,567,255 2,567,255   2,341,111     2,270,261
Conversion of Stock Exchange Ratio         65.36            
Preferred Stock, Liquidation Preference Per Share (in dollars per share) | $ / shares       $ 1,000 $ 1,000 $ 1,000          
Conversion of Stock, Conversion Rate (in dollars per share) | $ / shares       $ 15.30 $ 15.30 $ 15.30          
Series C Preferred Stock [Member]                      
Preferred Stock, Shares Outstanding, Ending Balance (in shares)       0 0 0 0 0      
Convertible Preferred Stock, Shares Issued upon Conversion (in shares)       1 1 1          
Conversion of Stock Exchange Ratio         1            
Series C Preferred Stock [Member] | January 2021 Offering [Member]                      
Convertible Preferred Stock, Shares Issued upon Conversion (in shares) 1           1        
Stock Issued During Period, Shares, New Issues (in shares) 2,450,880                    
[1] The condensed consolidated balance sheet as of December 31, 2020 has been derived from the audited consolidated financial statements as of that date.