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Stock-Based Compensation - Summary of Estimate the Fair Value of Stock Options Granted (Detail)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2017
Share-based Goods and Nonemployee Services Transaction [Line Items]    
Risk-free interest rate 210.00%  
Expected term (in years) 2 years 7 months 6 days 6 years 6 months
Expected volatility 5500.00%  
Expected dividend yield 0.00% 0.00%
Minimum    
Share-based Goods and Nonemployee Services Transaction [Line Items]    
Risk-free interest rate   1.90%
Expected volatility   38.10%
Maximum    
Share-based Goods and Nonemployee Services Transaction [Line Items]    
Risk-free interest rate   2.20%
Expected volatility   40.60%