Quarterly report pursuant to Section 13 or 15(d)

Convertible Preferred Stock and Stockholders' Equity - securities purchase agreement (Details)

v3.21.1
Convertible Preferred Stock and Stockholders' Equity - securities purchase agreement (Details) - USD ($)
Nov. 09, 2020
Jun. 09, 2020
Jun. 04, 2020
May 18, 2020
Mar. 31, 2021
Feb. 06, 2020
Apr. 18, 2019
Class of Stock [Line Items]              
Issuance of common stock and warrants, net of offering costs (in shares) 236,375     60,250      
Warrants to purchase shares of Common Stock           4,553 12,756
Exercise price of warrants $ 2.55            
Securities Purchase Agreement              
Class of Stock [Line Items]              
Issuance of common stock and warrants, net of offering costs (in shares)     2,275,000        
Warrant term     5 years 6 months        
Warrants to purchase shares of Common Stock     2,275,000        
June 4th Purchase Agreement              
Class of Stock [Line Items]              
Warrants to purchase shares of Common Stock         2,275,000    
Exercise price of warrants         $ 2.55    
June 4th Purchase Agreement | Securities Purchase Agreement              
Class of Stock [Line Items]              
Exercise price of warrants     $ 2.55        
Gross proceeds from offering     $ 5,801,000        
Cash fees paid     $ 464,000        
Cash fees paid percentage     8.00%        
June 8th Purchase Agreement              
Class of Stock [Line Items]              
Warrants to purchase shares of Common Stock         2,040,000    
Exercise price of warrants         $ 2.61    
June 9th Purchase Agreement | Securities Purchase Agreement              
Class of Stock [Line Items]              
Issuance of common stock and warrants, net of offering costs (in shares)   2,040,000          
Warrant term   5 years 6 months          
Warrants to purchase shares of Common Stock   2,040,000          
Exercise price of warrants   $ 2.61          
Gross proceeds from offering   $ 5,324,000          
Cash fees paid   $ 426,000          
Cash fees paid percentage   8.00%