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Stock-Based Compensation - Summary of Options Granted (Details) - $ / shares
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Granted (in shares) 24,208 23,218 14,755
Weighted average assumptions used in the fair value model:      
Weighted average market price on date of grants (in usd per share) $ 28.22    
Per share weighted average fair value (in usd per share) $ 8.41    
Stock options      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Term in years 10 years 10 years 10 years
Weighted average assumptions used in the fair value model:      
Fair value as a percentage of market value at grant date 30.00% 29.00% 35.00%
Weighted Average | Stock options      
Weighted average assumptions used in the fair value model:      
Expected volatility 37.00% 33.00% 37.00%
Expected dividend yield 3.43% 2.75% 2.10%
Expected life in years 6 years 6 months 6 years 6 months 6 years 6 months
Risk-free interest rate 1.02% 2.58% 2.86%
Weighted average market price on date of grants (in usd per share) $ 28.22 $ 29.84 $ 34.33
Per share weighted average fair value (in usd per share) $ 8.41 $ 8.70 $ 11.98