Annual report pursuant to Section 13 and 15(d)

Warrant Liability - Weighted-average key assumptions (Details)

v3.21.1
Warrant Liability - Weighted-average key assumptions (Details)
Mar. 03, 2020
Jan. 07, 2020
Dec. 31, 2019
Aug. 07, 2019
January 2020 Private Placement Warrant | Expected volatility        
Class of Warrant or Right [Line Items]        
Warrants and rights outstanding 124 121    
January 2020 Private Placement Warrant | Risk-free interest rate        
Class of Warrant or Right [Line Items]        
Warrants and rights outstanding 0.8 1.6    
January 2020 Private Placement Warrant | Expected term (in years)        
Class of Warrant or Right [Line Items]        
Warrants and rights outstanding 4.9 5.0    
January 2020 Private Placement Warrant | Weighted-average fair value per share warrant        
Class of Warrant or Right [Line Items]        
Warrants and rights outstanding 7.80 5.70    
August 2019 Placement Warrants | Expected volatility        
Class of Warrant or Right [Line Items]        
Warrants and rights outstanding 124   125  
August 2019 Placement Warrants | Risk-free interest rate        
Class of Warrant or Right [Line Items]        
Warrants and rights outstanding 0.8   1.7  
August 2019 Placement Warrants | Expected term (in years)        
Class of Warrant or Right [Line Items]        
Warrants and rights outstanding 4.5   4.6  
August 2019 Placement Warrants | Weighted-average fair value per share warrant        
Class of Warrant or Right [Line Items]        
Warrants and rights outstanding 6.30   3.30  
Placement Warrants | August 2019 Offering | Expected volatility        
Class of Warrant or Right [Line Items]        
Warrants and rights outstanding     125 87
Placement Warrants | August 2019 Offering | Risk-free interest rate        
Class of Warrant or Right [Line Items]        
Warrants and rights outstanding     1.7 1.5
Placement Warrants | August 2019 Offering | Dividend yield        
Class of Warrant or Right [Line Items]        
Warrants and rights outstanding     0.0 0.0
Placement Warrants | August 2019 Offering | Expected term (in years)        
Class of Warrant or Right [Line Items]        
Warrants and rights outstanding     4.6 4.9
Placement Warrants | August 2019 Offering | Weighted-average fair value per share warrant        
Class of Warrant or Right [Line Items]        
Warrants and rights outstanding     3.30 15.00