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Incentive Compensation - Additional Information (Details) - USD ($)
3 Months Ended
Mar. 18, 2019
Jan. 14, 2019
Mar. 31, 2019
Mar. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Stock-based compensation expense     $ 7,602,000 $ 6,265,000
Equity Incentive Plan [Member] | Full Value Awards [Member]        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Shares available for grant     8,552,820  
2018 Performance Program [Member]        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Performance measurement period, term   3 years    
Performance measurement period, start date   Jan. 01, 2019    
Performance measurement period, end date   Dec. 31, 2021    
Fair value of awards granted   $ 8,106,000    
Vesting period   4 years    
2018 Performance Program [Member] | Share-Based Compensation Award Tranche One [Member]        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Percentage of the awards that vest   50.00%    
2018 Performance Program [Member] | Share-Based Compensation Award Tranche Two [Member]        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Percentage of the awards that vest   50.00%    
2015 Performance Program [Member]        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Performance measurement period, units forfeited 1,109,358      
Fair value granted     $ 10,914,000  
Unrecognized compensation cost     $ 1,027,000  
Unrecognized compensation cost expected to be recognized over a weighted-average period     1 year