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Stock-Based Compensation - Additional Information (Detail) - USD ($)
3 Months Ended 103 Months Ended
Mar. 31, 2020
Mar. 31, 2019
Dec. 31, 2019
Jun. 06, 2011
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Common stock reserved for future issuance 10,123,483      
Unrecognized compensation expense related to stock options $ 0      
Restricted Stock Units (RSUs)        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Unrecognized compensation expense $ 3,700,000      
Unrecognized stock-based compensation expense, weighted average period of recognition 2 years 7 months 6 days      
Repurchase of common stock (in shares) 48,335 42,880    
2011 Plan        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Common stock reserved for future issuance       400,000
Number of shares available for grant       859,956
Increase in shares of common stock authorized for issuance     3,500,000  
2007 Plan and 2010 Plan        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Number of shares available for grant       459,956