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Share-Based and Other Compensation - 2019, 2018 and 2017 Annual Performance-Based RSU Grants (Details) - USD ($)
$ / shares in Units, $ in Millions
1 Months Ended 12 Months Ended
Feb. 01, 2019
Dec. 27, 2018
Feb. 14, 2018
Feb. 24, 2017
Feb. 28, 2019
Dec. 31, 2019
2019 Performance-Based RSUs [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Award vesting period           3 years
Vesting criteria, one           100.00%
Vesting criteria, two           50.00%
Vesting criteria, three           50.00%
Performance-based RSUs achievement target, participant one, percent           175.00%
Performance-based RSUs achievement target, all other participants, percent           150.00%
Fair value RSUs granted $ 10.2   $ 10.8      
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]            
Fair value per share on valuation date (in dollars per share) $ 72.57   $ 70.08      
2018 Performance-Based RSUs [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Award vesting period           3 years
Vesting criteria, two           50.00%
Vesting criteria, three           50.00%
Performance-based RSUs achievement target, participant one, percent           175.00%
Performance-based RSUs achievement target, all other participants, percent           150.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]            
Expected share price volatility (in dollars per share) 19.00%   20.00%      
Risk-free interest rate 2.48%   2.37%      
2017 Performance-Based RSUs [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Award vesting period           3 years
Vesting criteria, one           100.00%
Vesting criteria, two           30.00%
Vesting criteria, three           40.00%
Performance-based RSUs achievement target, percent           131.00%
Fair value RSUs granted       $ 10.3    
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]            
Fair value per share on valuation date (in dollars per share)       $ 80.89    
Expected share price volatility (in dollars per share)       21.00%    
Risk-free interest rate       1.39%    
Market measure-based Restricted Stock Units (RSUs) [Member]            
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]            
Fair value per share on valuation date (in dollars per share)           $ 71.12
Executive officer share-based compensation programs [Member] | Market measure-based Restricted Stock Units (RSUs) [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Grants in period (in shares) 143,396 80,647 158,205 130,956 143,396  
Market measure-based RSU estimate of probable [Member] | 2019 Performance-Based RSUs [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Estimated RSUs earned based on FFO           229,095
Target level of achievement, one           125.00%
Target level of achievement, two           117.00%
Market measure-based RSU estimate of probable [Member] | 2018 Performance-Based RSUs [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Estimated RSUs earned based on FFO           262,242
Market measure-based RSU estimate of probable [Member] | Market measure-based Restricted Stock Units (RSUs) [Member]            
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]            
Estimated RSUs earned based on FFO 229,095   262,242 142,581   142,581