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Stockholders' Equity - Additional Information (Detail) - USD ($)
Feb. 03, 2021
Jul. 22, 2020
Apr. 22, 2020
Dec. 31, 2020
Dec. 31, 2019
Jul. 24, 2019
Feb. 06, 2019
Jul. 25, 2018
Sep. 06, 2013
Class Of Stock [Line Items]                  
Preferred stock, par value       $ 0.01 $ 0.01        
Percentage of beneficial ownership required to exercise the right under Rights agreement, Description     10% (12% for passive investors, subject to the Excluded Persons exception below) or more            
Percentage of discount on purchase of additional share in Right agreement     50.00%            
Percentage of acquisition in merger or other unapproved party description     more than 10% (12% for passive investors, subject to the Excluded Persons exception below)            
Percentage of discount on share acquisition in merger or other unapproved party     50.00%            
Percentage of beneficial ownership not exercisable prior to adoption of Right agreement, Description     10% (12% for passive investors, subject to the Excluded Persons exception below) or more            
Redemption price of rights     $ 0.001            
Rights agreement outstanding common stock acquisition percentage description   20% or more              
Rights agreement common stock holding percentage description   4.9% or more              
Expire period of Right agreement     Apr. 21, 2021            
2013 program                  
Class Of Stock [Line Items]                  
Increase of the authorization under the stock buyback program           $ 250,000,000 $ 250,000,000 $ 250,000,000  
Remaining amount approved for repurchases under stock buyback program       $ 130,000,000          
2013 program | Maximum                  
Class Of Stock [Line Items]                  
Amount approved for repurchases under stock buyback program                 $ 200,000,000
Subsequent Event | Dividend Declared                  
Class Of Stock [Line Items]                  
Dividend declaration date Feb. 03, 2021                
Dividend per share, declared $ 0.02                
Dividend payment date Mar. 18, 2021                
Dividend record date Mar. 04, 2021                
Series A Junior Participating Preferred Stock                  
Class Of Stock [Line Items]                  
Preferred stock, par value     $ 0.01            
Preferred stock, exercise price per right     $ 17.00