Quarterly report pursuant to Section 13 or 15(d)

Stockholders' Equity - Narrative (Details)

v3.21.2
Stockholders' Equity - Narrative (Details) - USD ($)
$ / shares in Units, $ in Millions
1 Months Ended 3 Months Ended 9 Months Ended 38 Months Ended
Jun. 25, 2021
May 20, 2021
Apr. 01, 2020
Aug. 31, 2021
Aug. 31, 2018
Sep. 30, 2021
Sep. 30, 2021
Sep. 30, 2021
Dec. 31, 2020
Apr. 30, 2020
Nov. 30, 2019
Jan. 31, 2019
Jun. 30, 2016
Class of Stock [Line Items]                          
Common stock, shares authorized (in shares)           300,000,000 300,000,000 300,000,000 300,000,000        
Common stock, shares issued (in shares)           71,504,630 71,504,630 71,504,630 56,002,815        
Common stock, shares outstanding (in shares)           71,504,630 71,504,630 71,504,630 56,002,815        
Par value of common stock (USD per share)           $ 0.001 $ 0.001 $ 0.001 $ 0.001        
Preferred stock, shares authorized (in shares)           10,000,000 10,000,000 10,000,000 10,000,000        
Preferred stock, shares issued (in shares)           15,617 15,617 15,617 14,429        
Preferred stock, shares outstanding (in shares)           15,617 15,617 15,617 14,429        
Par value of preferred stock (USD per share)           $ 0.001 $ 0.001 $ 0.001 $ 0.001        
Jefferies LLC                          
Class of Stock [Line Items]                          
Par value of common stock (USD per share)       $ 0.001                  
At the market offering                          
Class of Stock [Line Items]                          
Sale of stock, authorized amount         $ 50.0                
Shares of stock sold, net consideration               $ 23.2          
At the market offering | Jefferies LLC                          
Class of Stock [Line Items]                          
Sale of stock, authorized amount       $ 50.0                  
At the market offering 1 | Jefferies LLC                          
Class of Stock [Line Items]                          
Shares of stock sold (in shares)           4,600,000              
Shares of stock sold, net consideration           $ 24.0              
Shares of stock sold, price (USD per share)           $ 5.27 $ 5.27 $ 5.27          
At the market offering 2 | Jefferies LLC                          
Class of Stock [Line Items]                          
Shares of stock sold (in shares)             7,600,000            
Shares of stock sold, net consideration             $ 36.7            
Shares of stock sold, price (USD per share)           $ 4.86 $ 4.86 $ 4.86          
Common Stock | Biotechnology Value Fund, L.P.                          
Class of Stock [Line Items]                          
Shares of stock sold (in shares)     3,000,000                    
Common Stock | Stock exchange, shares from existing shareholders                          
Class of Stock [Line Items]                          
Shares of stock sold (in shares)   5,000,000                      
2020 Plan                          
Class of Stock [Line Items]                          
Shares of stock authorized pursuant to the 2020 Plan (in shares)           3,500,000 3,500,000 3,500,000          
Additional shares authorized (in shares) 2,250,000                        
2019 Plan                          
Class of Stock [Line Items]                          
Shares of stock terminated under the 2019 Plan (in shares)             1,579,678            
Series A Preferred Stock                          
Class of Stock [Line Items]                          
Preferred stock, shares issued (in shares)           85 85 85 2,907        
Preferred stock, shares outstanding (in shares)           85 85 85 2,907        
Series A Preferred Stock | Preferred Stock | Stock exchange, shares from existing shareholders                          
Class of Stock [Line Items]                          
Par value of preferred stock (USD per share)                         $ 0.001
Series B Preferred Stock                          
Class of Stock [Line Items]                          
Preferred stock, shares issued (in shares)           4,026 4,026 4,026 5,000        
Preferred stock, shares outstanding (in shares)           4,026 4,026 4,026 5,000        
Series B Preferred Stock | Preferred Stock | Stock exchange, shares from existing shareholders                          
Class of Stock [Line Items]                          
Par value of preferred stock (USD per share)                       $ 0.001  
Series C Preferred Stock                          
Class of Stock [Line Items]                          
Preferred stock, shares issued (in shares)           3,506 3,506 3,506 3,522        
Preferred stock, shares outstanding (in shares)           3,506 3,506 3,506 3,522        
Series C Preferred Stock | Preferred Stock | Stock exchange, shares from existing shareholders                          
Class of Stock [Line Items]                          
Par value of preferred stock (USD per share)                     $ 0.001    
Series D Preferred Stock                          
Class of Stock [Line Items]                          
Preferred stock, shares issued (in shares)           3,000 3,000 3,000 3,000        
Preferred stock, shares outstanding (in shares)           3,000 3,000 3,000 3,000        
Series D Preferred Stock | Preferred Stock                          
Class of Stock [Line Items]                          
Preferred stock, shares authorized (in shares)     3,000                    
Shares of stock sold (in shares)     3,000                    
Series E Preferred Stock                          
Class of Stock [Line Items]                          
Preferred stock, shares issued (in shares)           5,000 5,000 5,000 0        
Preferred stock, shares outstanding (in shares)           5,000 5,000 5,000 0        
Series E Preferred Stock | Preferred Stock                          
Class of Stock [Line Items]                          
Preferred stock, shares authorized (in shares)   5,000                      
Par value of preferred stock (USD per share)   $ 0.001                      
Stock issued upon conversion (in shares)   1,000                      
Common stock ownership limit (as a percent)   9.99%                      
Beneficial ownership limitation (as a percent)   19.99%                      
Notice period before increase of beneficial ownership limitation   61 days                      
Series E Preferred Stock | Preferred Stock | Stock exchange, shares from existing shareholders                          
Class of Stock [Line Items]                          
Par value of preferred stock (USD per share)                   $ 0.001      
Series E Preferred Stock | Preferred Stock | Preferred share exchange                          
Class of Stock [Line Items]                          
Shares of stock sold (in shares)   5,000