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Stock-based Compensation - Schedule of Fair Value Assumptions and Techniques for Stock Options (Detail)
3 Months Ended 9 Months Ended
Sep. 30, 2021
Sep. 30, 2020
Sep. 30, 2021
Sep. 30, 2020
Share-based Payment Arrangement [Abstract]        
Expected life (years) 0 years 5 years 3 months 18 days 5 years 4 months 24 days 5 years 2 months 12 days
Risk-free interest rate 0.00% 0.30% 1.00% 1.30%
Expected volatility 0.00% 47.00% 46.00% 44.00%
Expected dividend yield 0.00% 0.00% 0.00% 0.00%