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Shareholders' Equity - Additional Information (Details) - USD ($)
 12 Months Ended 72 Months Ended
May 17, 2019
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2019
May 01, 2019
Accelerated Share Repurchases [Line Items]            
Shares repurchased, authorized amount     $ 100,000,000.0      
Treasury stock shares (in shares)   15,451,000 13,797,000   15,451,000  
Fair value of common stock repurchased   $ 536,243,000 $ 477,572,000   $ 536,243,000  
Stock repurchase program, remaining authorized repurchase amount   $ 461,300,000     $ 461,300,000  
Treasury stock, shares, acquired         15,500,000  
Accelerated Share Repurchase Agreement            
Accelerated Share Repurchases [Line Items]            
Treasury stock shares (in shares)   1,087,914   2,883,349 1,087,914  
Treasury stock, average cost per share   $ 35.55   $ 48.51    
Fair value of common stock repurchased   $ 38,700,000 $ 80,000,000.0 $ 139,900,000 $ 38,700,000  
Treasury stock, shares, acquired 566,599   2,910,150      
Maximum            
Accelerated Share Repurchases [Line Items]            
Shares repurchased, authorized amount   $ 100,000,000.0     $ 100,000,000.0 $ 372,500,000