Quarterly report pursuant to Section 13 or 15(d)

Stock-based Compensation - Stock Option Activity (Detail)

v3.21.2
Stock-based Compensation - Stock Option Activity (Detail) - USD ($)
$ / shares in Units, $ in Thousands
9 Months Ended 12 Months Ended
Sep. 30, 2021
Dec. 31, 2020
Number of Shares    
Beginning balance - Outstanding (shares) 830,343  
Granted (shares) 838,750  
Forfeited/Cancelled (shares) (25,587)  
Ending balance - Outstanding (shares) 1,643,506 830,343
Exercisable (shares) 674,795  
Vested or expected to vest (shares) 1,643,506  
Weighted- Average Exercise Price    
Beginning balance - Outstanding (in dollars per share) $ 21.52  
Granted (in dollars per share) 7.36  
Forfeited/Cancelled (in dollars per share) 6.68  
Ending balance - Outstanding (in dollars per share) 14.52 $ 21.52
Exercisable (in dollars per share) 24.03  
Vested or expected to vest (in dollars per share) $ 14.52  
Weighted- Average Remaining Contractual Life (in years)    
Balance - Outstanding 8 years 2 months 12 days 7 years 8 months 15 days
Exercisable 6 years 10 months 2 days  
Vested or expected to vest 8 years 2 months 12 days  
Aggregate Intrinsic Value ($000)    
Balance - Outstanding $ 10 $ 96
Exercisable 0  
Vested and expected to vest $ 10