Annual report pursuant to Section 13 and 15(d)

Oxford Finance Loan Agreement - Additional Information (Details)

v3.22.0.1
Oxford Finance Loan Agreement - Additional Information (Details)
12 Months Ended
Dec. 23, 2020
USD ($)
$ / shares
shares
Feb. 12, 2020
USD ($)
$ / shares
shares
Dec. 31, 2021
USD ($)
shares
Dec. 31, 2020
shares
Dec. 31, 2019
shares
Debt Instrument [Line Items]          
Warrants to purchase common stock | shares     2,117,094 2,117,094 2,118,094
Loan Agreement          
Debt Instrument [Line Items]          
Term loan, aggregate principal amount   $ 60,000,000.0      
Additional term loan advances, description     A $20.0 million term loan (first tranche) was funded on February 12, 2020, and another $20.0 million term loan (second tranche) was funded on December 23, 2020. As of December 31, 2021, the final $20.0 million tranche remained available under the Loan Agreement, at the sole discretion of the Lender    
Term loan, interest rate terms     The term loan bears interest at an annual rate equal to the greater of (i) 7.75% and (ii) the sum of 5.98% and the greater of (A) one-month LIBOR or (B) 1.77%.    
Term loan, interest rate   7.75%      
Term loan, effective interest rate   5.98%      
Term loan, variable interest rate basis     one-month LIBOR    
Term loan, variable interest rate basis spread   1.77%      
Term loan, maturity date   Feb. 01, 2025      
Term loan, final payment fee percentage   5.00%      
Warrant exercisable period from date of issuance     5 years    
Interest expense     $ 3,900,000    
Loan Agreement | Advance Prepaid in First 12 Months          
Debt Instrument [Line Items]          
Term loan, prepayment fee, equal to percentage of the principal amount being prepaid   2.00%      
Loan Agreement | Advance Prepaid After 12 Months But Prior to 24 Months          
Debt Instrument [Line Items]          
Term loan, prepayment fee, equal to percentage of the principal amount being prepaid   1.00%      
Loan Agreement | Advance Prepaid After 24 Months But Prior to Maturity Date          
Debt Instrument [Line Items]          
Term loan, prepayment fee, equal to percentage of the principal amount being prepaid   0.50%      
Loan Agreement | First Loan Tranche          
Debt Instrument [Line Items]          
Term loan   $ 20,000,000.0      
Term Loan, facilities fee   $ 100,000      
Warrants to purchase common stock | shares   27,548      
Warrant exercise price of common stock per share | $ / shares   $ 7.26      
Fair value of warrants   $ 100,000      
Loan Agreement | First Loan Tranche | Expected volatility | Weighted Average          
Debt Instrument [Line Items]          
Fair value of weighted average volatility   75.43      
Loan Agreement | First Loan Tranche | Expected life (in years) | Weighted Average          
Debt Instrument [Line Items]          
Fair value of weighted expected term   5 years      
Loan Agreement | Second Loan Tranche          
Debt Instrument [Line Items]          
Term loan $ 20,000,000.0        
Term Loan, facilities fee $ 75,000        
Warrants to purchase common stock | shares 17,389        
Warrant exercise price of common stock per share | $ / shares $ 11.50        
Fair value of warrants $ 200,000        
Loan Agreement | Second Loan Tranche | Expected volatility | Weighted Average          
Debt Instrument [Line Items]          
Fair value of weighted average volatility 82.41        
Loan Agreement | Second Loan Tranche | Expected life (in years) | Weighted Average          
Debt Instrument [Line Items]          
Fair value of weighted expected term 5 years        
Loan Agreement | Final Loan Tranche          
Debt Instrument [Line Items]          
Each of available additional term loan advances     $ 20,000,000.0    
Loan Agreement | Third Loan Tranche          
Debt Instrument [Line Items]          
Term loan, facilities fee   $ 50,000