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Borrowings - Additional Information (Detail)
1 Months Ended 3 Months Ended 6 Months Ended
May 13, 2021
USD ($)
Tranche
Mar. 07, 2019
USD ($)
Feb. 28, 2023
USD ($)
Jun. 30, 2023
USD ($)
Jun. 30, 2022
USD ($)
Jun. 30, 2023
USD ($)
Jun. 30, 2022
USD ($)
Mar. 30, 2023
USD ($)
Dec. 31, 2022
USD ($)
Dec. 31, 2021
Debt Instrument [Line Items]                    
Outstanding principal plus all accrued and unpaid interest amount payable to lenders       $ 0   $ 0     $ 34,393,000  
Amortization of debt issuance costs and discount       1,998,000 $ 421,000 2,256,000 $ 799,000      
Deferred fees, fully paid     $ 5,800,000              
Other Liabilities                    
Debt Instrument [Line Items]                    
Interest rate, deferred fees                 12.75% 12.75%
Loan and Security Agreement                    
Debt Instrument [Line Items]                    
Fair value of loan payable                 $ 34,400,000  
Loan and Security Agreement | Level 3 Inputs | Secured Spread                    
Debt Instrument [Line Items]                    
Debt instrument, measurement input                 9.84  
Loan and Security Agreement | Level 3 Inputs | Risk Free Rate                    
Debt Instrument [Line Items]                    
Debt instrument, measurement input                 4.37  
Loan and Security Agreement | Level 3 Inputs | Secured Yield                    
Debt Instrument [Line Items]                    
Debt instrument, measurement input                 14.21  
Loan Agreement Amendment                    
Debt Instrument [Line Items]                    
Prepayment fee payable               $ 262,500    
Final payment payable under loan agreement               1,382,500    
Loan Agreement Amendment | GlaxoSmithKline Intellectual Property                    
Debt Instrument [Line Items]                    
Upfront payment $ 90,000,000.0                  
Loan Agreement Amendment | Hercules Capital Incorporated And Silicon Valley Bank And Other Lenders                    
Debt Instrument [Line Items]                    
Outstanding principal plus all accrued and unpaid interest amount payable to lenders               $ 35,400,000    
Term Loan | Loan and Security Agreement                    
Debt Instrument [Line Items]                    
Basis spread on variable rate (as a percent) 9.05%                  
Term Loan | Loan and Security Agreement | Prime Rate                    
Debt Instrument [Line Items]                    
Basis spread on variable rate (as a percent) 5.80%                  
Term Loan | Loan and Security Agreement | Hercules Capital Inc. and Silicon Valley Bank                    
Debt Instrument [Line Items]                    
Number of available tranches | Tranche 4                  
Term Loan | Loan Agreement Amendment                    
Debt Instrument [Line Items]                    
Face amount $ 60,000,000.0                  
Initial Tranche of Term Loan | Loan and Security Agreement                    
Debt Instrument [Line Items]                    
Additional borrowing amount available 20,000,000.0                  
Second Tranche of Term Loan | Loan and Security Agreement                    
Debt Instrument [Line Items]                    
Additional borrowing amount available 10,000,000.0                  
Third Tranche of Term Loan | Loan and Security Agreement                    
Debt Instrument [Line Items]                    
Additional borrowing amount available $ 5,000,000.0                  
Senior Convertible Note Purchase Agreement                    
Debt Instrument [Line Items]                    
Face amount   $ 16,000,000.0                
Notes maturity date   Mar. 15, 2025                
Date of issuance and sale of notes   Mar. 07, 2019                
Proceeds from debt, net of issuance costs   $ 14,700,000                
Payment of debt issuance costs   $ 1,300,000                
Senior convertible notes       11,200,000   11,200,000     $ 11,000,000.0  
Bifurcated embedded conversion option derivative liability       400,000   400,000     42,000,000  
Derivative, fair value       7,000,000.0   7,000,000.0        
Gain (loss) on fair value adjustment of derivative liability       42,000,000 200,000 (400,000) 1,200,000      
Amortization of debt issuance costs and discount       300,000 $ 200,000 300,000 $ 400,000      
Fair value of convertible debt and derivative liability       $ 12,100,000   $ 12,100,000     $ 10,800,000  
Interest rate   6.00%                
Payment terms           The March 2019 Notes bear interest at a rate of 6.0% per annum payable semiannually in arrears on March 15 and September 15 of each year, beginning September 15, 2019. The March 2019 Notes will mature on March 15, 2025, unless earlier converted, redeemed or repurchased.