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Incentive Plans - Narrative (Details) - USD ($)
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Unvested share-based compensation arrangements, compensation costs to be expensed   $ 50,400,000    
Related income tax benefit recognized in income $ 7,389,000 $ 4,383,000 $ 5,017,000  
Stock options exercised 12,345 21,200 0  
Option term 7 years      
Total intrinsic value of options exercised $ 500,000   $ 0 $ 0
Vesting scheme   Under these plans, one-half of each grant is generally exercisable after two years and the remainder after three years.    
Cash settled awards   $ 16,900,000 6,500,000 12,900,000
Incentive compensation plan expense   $ 34,100,000 $ 30,000,000.0 30,500,000
Share-based Compensation Award, Tranche One        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Vesting period 2 years      
Share-based Compensation Award, Tranche Two        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Vesting period 3 years      
2012 Long-Term Plan        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Maximum number of shares available for issuance   6,750,000    
Maximum number of shares available for issuance, annual rate   1.00%    
Number of shares available   2,100,000    
Option term 7 years      
Employee Stock Purchase Plan        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Compensation costs estimation   Compensation costs related to the ESPP were estimated based on the value of the 10% discount and the fair value of the option that provided for the refund of participant withholdings    
Annual Incentive Plan | Share-based Compensation Award, Tranche One        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Vesting percentage   50.00%    
Minimum        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Settlement period of phantom units 3 years      
Maximum        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Settlement period of phantom units 5 years      
Employee Stock Options        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Related income tax benefit recognized in income   $ 0   $ 0
Stock options exercised   0   0
Time Lapse Restricted Stock        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Fair value per share at grant date     $ 28.51  
Time Lapse Restricted Stock | Minimum        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Fair value per share at grant date $ 21.68 $ 25.69    
Time Lapse Restricted Stock | Maximum        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Fair value per share at grant date $ 28.16 $ 28.43 $ 28.84