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Stock-Based Compensation - Summary of Assumptions with Respect to the Black-Scholes Option Pricing Model (Detail) - $ / shares
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]      
Weighted-average risk-free interest rate 2.40% 2.80%  
Weighted-average dividend yield 0.00% 0.00%  
Expected volatility 49.70% 50.60%  
Expected term (in years) 5 years 5 years 0 years
Weighted-average fair value $ 2.95 $ 3.15