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Stock-Based Compensation - Schedule of Assumptions Used for LTIP and TSOP Grants (Details)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Average expected volatility rate 22.00% 23.00% 24.00%
Average risk-free interest rate 1.47% 2.56% 2.55%
LTIP      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Average expected option term, in years 7 years 6 months 7 years 2 months 12 days 7 years 2 months 12 days