General form of registration statement for all companies including face-amount certificate companies

Share-Based Compensation - Summary of Share Based Payment Award Stock Options Valuation Assumptions Under Black-Scholes Option Pricing Model (Detail)

v3.22.2
Share-Based Compensation - Summary of Share Based Payment Award Stock Options Valuation Assumptions Under Black-Scholes Option Pricing Model (Detail) - USD ($)
12 Months Ended
Dec. 31, 2021
Dec. 31, 2020
Schedule Of Share Based Payment Award Stock Options Valuation Assumptions [Line Items]    
Expected term   6 years 3 months
Expected volatility (Minimum)   110.00%
Expected volatility (Maximum)   120.00%
Expected dividend yield   $ 0
Risk-free interest rate (Minimum)   0.46%
Risk-free interest rate (Maximum)   0.56%
Prior to Cancellation Of PredaSAR Plan [Member]    
Schedule Of Share Based Payment Award Stock Options Valuation Assumptions [Line Items]    
Expected volatility (Minimum) 105.00%  
Expected volatility (Maximum) 105.00%  
Risk-free interest rate (Minimum) 0.95%  
Risk-free interest rate (Maximum) 0.95%  
Prior to Cancellation Of PredaSAR Plan [Member] | Minimum [Member]    
Schedule Of Share Based Payment Award Stock Options Valuation Assumptions [Line Items]    
Expected term 5 years 6 months  
Expected dividend yield $ 0  
Prior to Cancellation Of PredaSAR Plan [Member] | Maximum [Member]    
Schedule Of Share Based Payment Award Stock Options Valuation Assumptions [Line Items]    
Expected term 6 years 3 days  
Expected dividend yield $ 0