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Stock-Based Compensation Plans - Summary of Fair Value of Stock Options (Details) - Stock Options
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected stock price volatility, Minimum 31.00% 30.00%
Expected stock price volatility, Maximum 37.00% 32.00%
Expected term of options 4 years 6 months 4 years 6 months
Risk-free interest rate, Minimum 0.25% 2.22%
Risk-free interest rate, Maximum 1.41% 2.47%