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Stock-Based Compensation - Summary of Fair Values of Stock Options Granted and Assumptions used in Black-Scholes Model (Detail) - Stock Options [Member] - $ / shares
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Estimated fair values of stock options granted $ 3.61 $ 3.24 $ 10.18  
Minimum [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Risk-free interest rate 0.60% 0.30% 1.70%  
Expected volatility 80.10% 77.40% 52.60%  
Expected term (in years) 5 years 6 months 6 years 6 years 9 months 18 days 5 years 7 months 6 days
Maximum [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Risk-free interest rate 1.20% 1.70% 2.50%  
Expected volatility 91.00% 81.20% 78.90%  
Expected term (in years) 6 years 6 months 10 years 10 years 10 years