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Stock-Based Compensation - Additional Information (Detail) - USD ($)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Estimated fair value of stock options, vested $ 1,600,000 $ 2,000,000
Payment of cash dividends $ 0  
Dividend yield ratio 0.00%  
Intrinsic value of options exercised $ 0  
Tax benefits related to stock option exercised 0  
Unrecognized stock-based compensation cost related to unvested stock options $ 2,000,000  
Weighted average term of unrecognized stock-based compensation expense 2 years 3 months 18 days  
Maximum [Member]    
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]    
Intrinsic value of options exercised   $ 100,000