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Borrowings - Additional Information (Detail)
 1 Months Ended 3 Months Ended
May 13, 2021
USD ($)
Tranche
Mar. 07, 2019
USD ($)
Feb. 28, 2023
USD ($)
Mar. 31, 2024
USD ($)
Mar. 31, 2023
USD ($)
Dec. 31, 2023
USD ($)
Mar. 30, 2023
USD ($)
Dec. 31, 2022
Dec. 31, 2021
Debt Instrument [Line Items]                  
Amortization of debt issuance costs and discount       $ 401,000 $ 255,000        
Deferred fees, fully paid     $ 5,800,000            
Other Liabilities                  
Debt Instrument [Line Items]                  
Interest rate, deferred fees               12.75% 12.75%
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                
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 | Hercules Capital Inc. and Silicon Valley Bank                  
Debt Instrument [Line Items]                  
Face amount $ 60,000,000                
Number of available tranches | Tranche 4                
Senior Convertible Note Purchase Agreement                  
Debt Instrument [Line Items]                  
Face amount   $ 16,000,000              
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       12,400,000   $ 12,000,000      
Bifurcated embedded conversion option derivative liability       28,000   200,000      
Derivative, fair value       7,000,000          
Gain (loss) on fair value adjustment of derivative liability       200,000 (400,000)        
Amortization of debt issuance costs and discount       400,000 $ 0        
Fair value of convertible debt and derivative liability       $ 12,700,000   $ 12,700,000      
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.