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Equity Plans and Stock-Based Compensation - Fair Value-Based Measurements and Weighted-Average Assumptions (Detail) - $ / shares
3 Months Ended 6 Months Ended
Jun. 30, 2021
Jun. 30, 2020
Jun. 30, 2021
Jun. 30, 2020
Share-based Payment Arrangement, Option        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Weighted-average fair value per share $ 6.20 $ 3.77 $ 6.57 $ 3.61
Expected life (in years) 4 years 6 months 4 years 6 months 4 years 6 months 4 years 6 months
Volatility 0.90% 0.90% 1.00% 0.90%
Minimum | Share-based Payment Arrangement, Option        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Risk-free interest rate 0.90% 0.30% 0.60% 1.20%
Market Based Performance Stock Unit        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Weighted-average fair value per share     $ 8.40  
Expected life (in years)     2 years 10 months 24 days  
Volatility     0.90%  
Market Based Performance Stock Unit | Minimum        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Risk-free interest rate     0.03%  
Market Based Performance Stock Unit | Maximum        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Risk-free interest rate     1.92%