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Treasury Stock - Additional Information (Detail) - USD ($)
3 Months Ended
Mar. 31, 2021
Sep. 30, 2020
Jun. 30, 2020
Mar. 31, 2020
Dec. 31, 2020
Equity, Class of Treasury Stock [Line Items]          
Treasury stock, shares repurchased value   $ 61,349,000 $ 11,128,000 $ 50,747,000  
Treasury stock, shares 8,684,000       8,684,000
Treasury stock, cost $ 782,104,000       $ 782,104,000
Class A          
Equity, Class of Treasury Stock [Line Items]          
Treasury stock, shares repurchased   0 0 0  
Treasury stock, shares repurchased value   $ 0 $ 0 $ 0  
Class A | Share Repurchase Program          
Equity, Class of Treasury Stock [Line Items]          
Shares repurchased program expiration date Apr. 29, 2023        
Stock authorized to repurchase by board of directors $ 800,000,000.0        
Treasury stock, shares repurchased 0     354,633  
Shares repurchased, average price per share       $ 143.10  
Treasury stock, shares repurchased value       $ 50,700,000  
Treasury stock, shares 5,674,226        
Shares repurchased, average price per share $ 104.13        
Treasury stock, cost $ 590,900,000        
Stock remaining available for repurchase $ 209,100,000