Annual report pursuant to Section 13 and 15(d)

Consolidated Statements of Stockholders' Equity (Parentheticals)

v3.22.1
Consolidated Statements of Stockholders' Equity (Parentheticals) - $ / shares
Dec. 31, 2021
Dec. 31, 2020
Common Stock [Member] | March 2021 Offering [Member]    
Stock issued, price per share (in dollars per share) $ 9.00  
Common Stock [Member] | February 2021 Offering [Member]    
Stock issued, price per share (in dollars per share) 4.10  
Common Stock [Member] | January 2021 Offering [Member]    
Stock issued, price per share (in dollars per share) 2.60  
Common Stock [Member] | May 2020 Offering [Member]    
Stock issued, price per share (in dollars per share)   $ 3.50
Common Stock [Member] | August 2020 Offering [Member]    
Stock issued, price per share (in dollars per share)   1.85
Additional Paid-in Capital [Member] | March 2021 Offering [Member]    
Stock issued, price per share (in dollars per share) 9.00  
Additional Paid-in Capital [Member] | February 2021 Offering [Member]    
Stock issued, price per share (in dollars per share) 4.10  
Additional Paid-in Capital [Member] | January 2021 Offering [Member]    
Stock issued, price per share (in dollars per share) $ 2.60  
Additional Paid-in Capital [Member] | May 2020 Offering [Member]    
Stock issued, price per share (in dollars per share)   3.50
Additional Paid-in Capital [Member] | August 2020 Offering [Member]    
Stock issued, price per share (in dollars per share)   $ 1.85