Quarterly report pursuant to Section 13 or 15(d)

Warrants (Details)

v3.22.1
Warrants (Details) - USD ($)
$ / shares in Units, $ in Millions
 3 Months Ended
Feb. 28, 2022
Jan. 28, 2022
Sep. 13, 2021
Feb. 16, 2021
Feb. 12, 2021
Feb. 11, 2021
Jan. 24, 2021
Mar. 31, 2022
Dec. 31, 2021
Class of Warrant or Right [Line Items]                  
Common stock, par value (in usd per share)               $ 0.001 $ 0.001
Number of shares sold under offering (in shares)           3,000,000      
Number of securities called by warrants or rights (in shares) 49,305,088 49,305,088              
Warrants exercised (in shares) 13,811,407 13,811,407              
Assumptions, fair value of existing warrants per share (in usd per share)   $ 0.16              
Warrants forfeited (in shares)               29,550,000  
Warrants outstanding (in shares)               17,450,000  
Preferred stock, shares authorized (in shares)               5,000,000 5,000,000
Preferred stock, par value (in usd per share)               $ 0.001 $ 0.001
Series 7 Convertible Preferred Stock                  
Class of Warrant or Right [Line Items]                  
Mezzanine equity, convertible preferred shares, par value per share (in usd per share)     $ 0.001            
Series 7 Preferred redeemed for cash (in shares)               49,250  
Series 7 Preferred redeemed for cash               $ 49.3  
Series 8 Convertible Preferred Stock                  
Class of Warrant or Right [Line Items]                  
Number of shares sold under offering (in shares)               112,778,720  
Subscription price (in usd per share)               $ 940  
Original issuance discount percentage               6.00%  
Aggregate subscription value               $ 50.0  
Preferred stock, shares authorized (in shares)               53,197.7234  
Preferred stock, par value (in usd per share)               $ 0.001  
Purchase Warrants                  
Class of Warrant or Right [Line Items]                  
Exercisable warrants per common share (in shares)       1 1   1    
January 2021 Warrants                  
Class of Warrant or Right [Line Items]                  
Common stock issued in direct offering (in shares)               13,554,838  
February 2021 Pre-Funded Warrants                  
Class of Warrant or Right [Line Items]                  
Common stock issued in direct offering (in shares)               8,000,000  
Warrants to purchase shares of common stock (in shares)         8,000,000        
Offering price (in usd per share)         $ 1.999        
Second February 2021 Pre-Funded Warrants                  
Class of Warrant or Right [Line Items]                  
Common stock issued in direct offering (in shares)               6,950,250  
Warrants to purchase shares of common stock (in shares)       6,950,250          
Offering price (in usd per share)       $ 2.009          
Existing Warrants                  
Class of Warrant or Right [Line Items]                  
Number of securities called by warrants or rights (in shares) 3,938,424 3,938,424              
Registered Direct Offering                  
Class of Warrant or Right [Line Items]                  
Common stock issued in direct offering (in shares)       3,000,000 7,000,000   5,800,000    
Subscription price (in usd per share)     $ 920            
Original issuance discount percentage     8.00%            
Aggregate subscription value     $ 54.1            
Registered Direct Offering | Series 7 Convertible Preferred Stock                  
Class of Warrant or Right [Line Items]                  
Number of shares sold under offering (in shares)     58,750            
Subscription price (in usd per share)     $ 920            
Original issuance discount percentage     8.00%            
Aggregate subscription value     $ 54.1            
Registered Direct Offering | Common Stock                  
Class of Warrant or Right [Line Items]                  
Number of shares sold under offering (in shares)     47,000,000            
Registered Direct Offering | January 2021 Pre-Funded Warrants                  
Class of Warrant or Right [Line Items]                  
Warrants to purchase shares of common stock (in shares)             3,000,000    
Offering price (in usd per share)             $ 1.549    
Exercisable warrants per common share (in shares)             1    
Warrants                  
Class of Warrant or Right [Line Items]                  
Warrants to purchase shares of common stock (in shares)       9,950,250 15,000,000   19,354,838    
Exercise price of warrants (in usd per share)               $ 0.001  
Percent of warrants forfeited upon redemption     75.00%            
Warrants | Series 7 Convertible Preferred Stock                  
Class of Warrant or Right [Line Items]                  
Percent of warrants forfeited upon redemption               75.00%  
Warrants | Series 8 Convertible Preferred Stock                  
Class of Warrant or Right [Line Items]                  
Percent of warrants forfeited upon redemption               50.00%  
Warrants | Purchase Warrants                  
Class of Warrant or Right [Line Items]                  
Offering price (in usd per share)       $ 2.01 $ 2.00   $ 1.55    
Exercise price of warrants (in usd per share)       $ 2.01 $ 2.00   $ 1.55    
Warrants | January 2021 Warrants                  
Class of Warrant or Right [Line Items]                  
Warrants exercised for common shares (in shares)               13,554,838  
Warrants | February 2021 Pre-Funded Warrants                  
Class of Warrant or Right [Line Items]                  
Warrants exercised for common shares (in shares)               8,000,000  
Warrants | Second February 2021 Pre-Funded Warrants                  
Class of Warrant or Right [Line Items]                  
Warrants exercised for common shares (in shares)               6,950,250  
Warrants | Registered Direct Offering                  
Class of Warrant or Right [Line Items]                  
Common stock issued in direct offering (in shares)       3,000,000 7,000,000   5,800,000    
Common stock, par value (in usd per share)         $ 0.001   $ 0.001    
Number of shares sold under offering (in shares)     47,000,000            
Warrants | Registered Direct Offering | Purchase Warrants                  
Class of Warrant or Right [Line Items]                  
Warrant and rights outstanding, term       5 years 5 years   5 years    
Warrants | Registered Direct Offering | January 2021 Pre-Funded Warrants                  
Class of Warrant or Right [Line Items]                  
Exercise price of warrants (in usd per share)       $ 0.001 $ 0.001   $ 0.001