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Stock-Based Compensation - Additional Information (Details) - USD ($)
1 Months Ended 12 Months Ended
Sep. 19, 2017
May 31, 2017
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Share units performance period     3 years    
Stock-based compensation     $ 7,588,000 $ 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     $ 500,000 $ 400,000  
Shares available for issuance under ESPP     2,800,000    
Stock issued during period shares share based compensation     100,000 100,000  
RSUs          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Weighted average grant-date fair value of RSUs granted     $ 23.51 $ 26.63  
Aggregate fair value of share appreciation rights vested     $ 7,100,000 $ 3,700,000  
Number of share units granted     582,000    
PSUs          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Number of share units granted     212,000    
PSUs | Certain Employees | DI          
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       3 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     200.00%    
Maximum | PSUs | Tranche Two          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Share units vesting percentage       150.00%  
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     15,100,000    
Omnibus Plan | Maximum          
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]          
Common stock shares issued   18,000,000