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Stock-Based Compensation - Additional Information (Detail) - USD ($)
1 Months Ended 3 Months Ended 6 Months Ended
Jun. 30, 2019
Jun. 30, 2020
Jun. 30, 2019
Jun. 30, 2020
Jun. 30, 2019
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]          
Share based compensation by share based payment arrangement weighted average fair value per share of stock options granted       $ 14.81  
Unrecognised compensation realting to stock options not vested   $ 13,800,000   $ 13,800,000  
Share based compensation non vested award period of recognition       2 years 9 months 18 days  
Share based compensation by share based payment arrangement instruments other than options granted       14,945  
Share based compensation by share based payment arrangement instruments other than options granted weighted average grant date fair value       $ 14.81  
Allocated share based compensation expense   1,157,000 $ 803,000 $ 2,898,000 $ 1,362,000
Performance Based Restricted Stock Units [Member]          
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]          
Share based compensation by share based payment arrangement instruments other than options granted 567,509        
Share based compensation by share based payment arrangement instruments other than options granted weighted average grant date fair value $ 13.37        
Allocated share based compensation expense   $ 0 $ 0 $ 0 $ 0
2011 Plan [Member]          
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]          
Share based payment arrangement, shares authorized for issuance   3,858,099   3,858,099  
Share based payment arrangement number of shares available for issuance   390,912   390,912  
Share based compensation by share based payment arrangement stock options vesting term       4 years  
Share based compensation by share based payment arrangement stock options contractual term       10 years