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Stock-Based Compensation (Details 2) - Employee Stock Option [Member]
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Dividend yield
Expected life 7 years 7 years 7 years
Expected volatility 25.51% 28.21% 32.07%
Risk-free interest rate 1.29% 2.59% 2.50%