Quarterly report pursuant to Section 13 or 15(d)

Capitalization and Equity Structure - Warrants (Details)

v3.20.2
Capitalization and Equity Structure - Warrants (Details) - $ / shares
shares in Thousands
1 Months Ended 9 Months Ended
Jun. 30, 2019
Dec. 31, 2015
Sep. 30, 2020
Jun. 30, 2020
Dec. 31, 2019
Class Of Warrant Or Right, Outstanding [Roll Forward]          
Beginning balance (in shares)     1,178    
Warrants issued (in shares)     996    
Exercised (in shares)     (723)    
Expired (in shares)     (19)    
Ending balance (in shares)     1,432    
June 2020 Investor Warrants          
Schedule of Capitalization, Equity [Line Items]          
Exercise price (in dollars per share)     $ 5.18    
Term (Years)     5 years 6 months    
Class Of Warrant Or Right, Outstanding [Roll Forward]          
Beginning balance (in shares)     0    
Warrants issued (in shares)     874    
Exercised (in shares)     (477)    
Expired (in shares)     0    
Ending balance (in shares)     397    
June 2020 Placement Agent Warrants          
Schedule of Capitalization, Equity [Line Items]          
Exercise price (in dollars per share)     $ 5.64 $ 5.64  
Term (Years)     5 years    
Class Of Warrant Or Right, Outstanding [Roll Forward]          
Beginning balance (in shares)     0    
Warrants issued (in shares) 122   122    
Exercised (in shares)     0    
Expired (in shares)     0    
Ending balance (in shares)     122    
December 2019 Warrants          
Schedule of Capitalization, Equity [Line Items]          
Exercise price (in dollars per share)     $ 8.10    
Term (Years)     5 years    
Class Of Warrant Or Right, Outstanding [Roll Forward]          
Beginning balance (in shares)     556    
Warrants issued (in shares)     0    
Exercised (in shares)     0    
Expired (in shares)     0    
Ending balance (in shares)     556    
December 2019 Placement Agent Warrants          
Schedule of Capitalization, Equity [Line Items]          
Exercise price (in dollars per share)     $ 8.44    
Term (Years)     5 years    
Class Of Warrant Or Right, Outstanding [Roll Forward]          
Beginning balance (in shares)     52    
Warrants issued (in shares)     0    
Exercised (in shares)     0    
Expired (in shares)     0    
Ending balance (in shares)     52    
May 2019 Warrants          
Schedule of Capitalization, Equity [Line Items]          
Exercise price (in dollars per share)     $ 3.52    
Term (Years)     5 years    
Class Of Warrant Or Right, Outstanding [Roll Forward]          
Beginning balance (in shares) 444   444    
Warrants issued (in shares)     0    
Exercised (in shares)     (246)    
Expired (in shares)     0    
Ending balance (in shares)     198    
2017 Information Agent Warrants          
Schedule of Capitalization, Equity [Line Items]          
Exercise price (in dollars per share)     $ 22.50    
Term (Years)     3 years    
Class Of Warrant Or Right, Outstanding [Roll Forward]          
Beginning balance (in shares)     13    
Warrants issued (in shares)     0    
Exercised (in shares)     0    
Expired (in shares)     (13)    
Ending balance (in shares)     0    
2015 Warrants          
Schedule of Capitalization, Equity [Line Items]          
Exercise price (in dollars per share)     $ 41.25   $ 56.10
Term (Years)     5 years    
Class Of Warrant Or Right, Outstanding [Roll Forward]          
Beginning balance (in shares)     107    
Warrants issued (in shares)   141 0    
Exercised (in shares)     0    
Expired (in shares)     0    
Ending balance (in shares)     107    
Pre-2014 warrants          
Schedule of Capitalization, Equity [Line Items]          
Exercise price (in dollars per share)     $ 144.90    
Class Of Warrant Or Right, Outstanding [Roll Forward]          
Beginning balance (in shares)     6    
Warrants issued (in shares)     0    
Exercised (in shares)     0    
Expired (in shares)     (6)    
Ending balance (in shares)     0    
Pre-2014 warrants | Minimum          
Schedule of Capitalization, Equity [Line Items]          
Term (Years)     9 years    
Pre-2014 warrants | Maximum          
Schedule of Capitalization, Equity [Line Items]          
Term (Years)     10 years