Annual report pursuant to Section 13 and 15(d)

Loans Payable (Details)

v3.20.4
Loans Payable (Details)
$ / shares in Units, $ in Thousands
1 Months Ended 12 Months Ended
Mar. 02, 2020
USD ($)
Sep. 30, 2014
USD ($)
tranche
$ / shares
shares
Dec. 31, 2020
USD ($)
shares
Dec. 31, 2019
USD ($)
Sep. 30, 2020
$ / shares
shares
Mar. 31, 2017
USD ($)
Dec. 31, 2015
$ / shares
shares
Long Term Debt              
Interest expense     $ 29 $ 931      
Amortization of debt discount and issuance costs       100      
Loan and security agreement              
Long Term Debt              
Maximum amount available   $ 35,000          
Debt number of tranches | tranche   3          
Gross proceeds           $ 28,500  
Final payment fee $ 1,900            
Final payment fee percentage 6.60%            
Term Loan A | Common Stock | Warrants              
Long Term Debt              
Number of shares that can be purchased upon exercise of warrants (in shares) | shares   7,678 5,728        
Exercise price | $ / shares   $ 5.8610          
Term Loan B | Common Stock | Warrants              
Long Term Debt              
Number of shares that can be purchased upon exercise of warrants (in shares) | shares             34,961
Exercise price | $ / shares             $ 10.6190
Term Loan C              
Long Term Debt              
Interest rate (as a percent)   6.98%          
Term Loan C | Common Stock | Warrants              
Long Term Debt              
Number of shares that can be purchased upon exercise of warrants (in shares) | shares         62,241    
Exercise price | $ / shares         $ 3.6150    
Term Loans A and B              
Long Term Debt              
Interest rate (as a percent)   6.50%          
Term Loans A, B, and C              
Long Term Debt              
Gross proceeds       3,167      
Aggregate principal balance outstanding     $ 0        
Interest expense     $ 20 $ 600      
Debt discount and debt issuance costs   $ 1,000