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Share-Based Compensation - Schedule of Weighted Average Performance Share Units Fair Values and Assumptions (Details) - Performance Shares Units - $ / shares
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Weighted average fair value of grants (in dollars per share) $ 207.26 $ 216.59 $ 115.74
Dividend yield 0.00% 0.00% 0.00%
Volatility 19.11% 17.42% 17.36%
Risk-free interest rate 2.49% 2.40% 1.45%
Expected life (in years) 2 years 9 months 29 days 2 years 10 months 6 days 2 years 10 months 6 days