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Stock-Based Compensation Plans - Additional Information (Details) - USD ($)
1 Months Ended 12 Months Ended
Oct. 31, 2017
May 31, 2017
Dec. 31, 2018
Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Number of share units granted     522,000  
Weighted-average grant-date fair value     $ 26.63  
Share units performance period     3 years  
Stock-based compensation expense     $ 9,423,000 $ 2,627,000
Employee Stock Purchase Plan        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Eligible employees payroll deductions percentage 10.00%      
Description of terms of award     Eligible employees  
Purchase price of common stock as percentage of market value 85.00%      
Stock-based compensation expense     $ 400,000  
Shares available for issuance under ESPP     2,900,000  
Stock issued during period shares share based compensation     100,000  
RSUs        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Weighted average grant-date fair value of RSUs granted     $ 26.63 $ 25.84
Aggregate fair value of share appreciation rights vested     $ 3,700,000 $ 1,800,000
PSUs        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Number of share units granted     780,000  
Weighted-average grant-date fair value     $ 27.41  
PSUs | Certain Employees        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Number of share units granted     632,000  
PSUs | Tranche One        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Award vesting period     3 years  
Share units performance period     3 years  
PSUs | Tranche Two        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Award vesting period     3 years  
Share units performance period     2 years  
Maximum | Employee Stock Purchase Plan        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Purchase price of common stock $ 10,000      
Shares available for issuance under ESPP     3,000,000  
Maximum | RSUs        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Award vesting period     4 years  
Maximum | PSUs | Tranche One        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Share units vesting percentage     150.00%  
Maximum | PSUs | Tranche Two        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Share units vesting percentage     200.00%  
Minimum | RSUs        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Award vesting period     1 year  
Minimum | PSUs | Tranche One        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Share units vesting percentage     0.00%  
Minimum | PSUs | Tranche Two        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Share units vesting percentage     0.00%  
Omnibus Plan        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Common stock shares available for future grants     15,700,000  
Omnibus Plan | Maximum        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Common stock shares issued   18,000,000