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Stock-Based Compensation - Fair Value of Stock Options Granted (Detail) - $ / shares
3 Months Ended
Mar. 31, 2022
Mar. 31, 2021
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Weighted average grant date fair value $ 1.16 $ 2.04
Assumptions used to determine fair value:    
Range of expected option life 6 years 6 years
Expected volatility 79.00%  
Expected dividend yield 0.00% 0.00%
Minimum [Member]    
Assumptions used to determine fair value:    
Expected volatility   80.00%
Risk-free interest rate 1.50% 0.70%
Maximum [Member]    
Assumptions used to determine fair value:    
Expected volatility   81.00%
Risk-free interest rate 2.40% 1.20%