Quarterly report pursuant to Section 13 or 15(d)

Oxford Finance Loan Agreement - Additional Information (Details)

v3.22.1
Oxford Finance Loan Agreement - Additional Information (Details)
3 Months Ended
Dec. 23, 2020
USD ($)
$ / shares
shares
Feb. 12, 2020
USD ($)
$ / shares
shares
Mar. 31, 2022
USD ($)
shares
Mar. 31, 2021
USD ($)
shares
Dec. 31, 2021
USD ($)
Debt Instrument [Line Items]          
Term loan     $ 40,000,000    
Warrants to purchase common stock | shares     2,117,094 2,117,094  
Current portion of debt     $ 1,667,000    
Long-term portion of debt     $ 38,775,000   $ 40,257,000
Loan Agreement          
Debt Instrument [Line Items]          
Term loan, aggregate principal amount   $ 60,000,000.0      
Additional term loan advances, description   A first tranche term loan for $20.0 million was funded on February 12, 2020, and a second tranche term loan for $20.0 million was funded on December 23, 2020. The remaining $20.0 million is still available under the Loan Agreement, at the sole discretion of the Lender.      
Each of available additional term loan advances   $ 20,000,000.0      
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%      
Warrants to purchase common stock | shares     27,548 27,548  
Warrant exercisable period from date of issuance     5 years    
Interest expense     $ 1,000,000.0 $ 900,000  
Current portion of debt     1,700,000    
Long-term portion of debt     $ 38,800,000    
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 | Third Loan Tranche          
Debt Instrument [Line Items]          
Term loan, facilities fee   $ 50,000