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Stock-Based Compensation - Schedule of Share-based Payment, Award, Stock Appreciation Rights, Valuation Assumptions (Details)
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Share-based Payment Arrangement [Abstract]      
Expected life (in years) 7 years 7 years 7 years
Expected volatility (as a percent) 24.00% 32.00% 35.00%
Expected dividend yield (as a percent) 3.20% 3.30% 1.90%
Risk-free interest rate 1.50% 2.60% 2.60%