Annual report pursuant to Section 13 and 15(d)

Borrowing Arrangements - Additional Information (Detail)

v3.20.1
Borrowing Arrangements - Additional Information (Detail) - USD ($)
 12 Months Ended 21 Months Ended
Feb. 27, 2018
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2016
Apr. 30, 2015
Debt Instrument [Line Items]          
Credit facility, amortization of debt discount   $ 486,000 $ 318,000    
Long-term debt, carrying value   3,700,000 3,300,000    
Perceptive          
Debt Instrument [Line Items]          
Final fee due at loan maturity date $ 3,400,000        
Total debt   $ 5,000,000 5,000,000    
Debt instrument, annual interest rate   12.90%      
Credit Facility, interest expense   $ 700,000 600,000    
Credit facility, amortization of debt discount   $ 300,000 300,000    
Term Loan Facility | Perceptive          
Debt Instrument [Line Items]          
Maximum borrowing capacity under loan $ 10,000,000        
Warrant exercise price $ 9.5792        
Increase in applicable margin percentage on event of default 4.00%        
Period for which interest only payments will be made 24 months        
Credit Facility, principal payments $ 200,000        
Credit Facility, maturity date Feb. 27, 2022        
Exit fee $ 100,000        
Deferred finance costs 500,000        
Debt issuance cost, net of discount $ 1,500,000        
Number of shares issued for each warrant 190,000        
Fair value of the warrant recorded as a debt discount $ 1,500,000        
Warrant exercisable period 7 years        
Term Loan Facility | Perceptive | LIBOR          
Debt Instrument [Line Items]          
Applicable margin percentage 11.00%        
SVB Growth Capital Loan          
Debt Instrument [Line Items]          
Debt instrument, frequency of periodic payment   3      
Maximum borrowing capacity under loan         $ 6,000,000
Number of warrants to purchase shares of common stock         48,874
Warrant exercise price         $ 3.07
Final fee due at loan maturity date         $ 400,000
Amount drew down from bank       $ 6,100,000  
Debt instrument principal paid during period     3,200,000    
Final fee paid     400,000    
Total debt     $ 0    
Term Loan Drawn on Effective Date of Credit Facility | Term Loan Facility | Perceptive          
Debt Instrument [Line Items]          
Proceeds from initial term loan on closing date of Credit Facility $ 5,000,000        
Additional Term Loan Drawn Six Months Following Effective Date of Credit Facility | Term Loan Facility | Perceptive          
Debt Instrument [Line Items]          
Remaining available amount from credit facility to be drawn six months following effective date of credit facility $ 5,000,000