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Summary of Significant Accounting Policies Stock-Based Compensation (Details) - $ / shares
1 Months Ended 3 Months Ended 12 Months Ended
Jan. 31, 2023
Mar. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award          
Number of shares authorized for issuance     9,000,000    
Stock options          
Share-based Compensation Arrangement by Share-based Payment Award          
Vesting period (in years)     3 years    
Minimum exercise price of stock option as a percent of common stock fair value on the grant date     100.00%    
Period after the grant date during which stock options can't be exercised (in months)     6 months    
Maximum term of awards (in years)     10 years    
Stock options granted (in shares)     437,269 530,612 554,594
Estimated weighted-average fair value per stock option (in dollars per share)     $ 14.71 $ 13.20 $ 10.94
Risk-free interest rate, minimum (as a percent)     0.20% 0.10% 0.20%
Risk-free interest rate, maximum (as a percent)     1.60% 0.90% 1.90%
Dividend yield (as a percent)     3.20% 2.90% 3.00%
Expected volatility (as a percent)     21.00% 21.00% 16.30%
Expected life (in years)     8 years 8 months 12 days 8 years 8 months 12 days 8 years 7 months 6 days
Stock options | Subsequent event          
Share-based Compensation Arrangement by Share-based Payment Award          
Stock options granted (in shares)   257,780      
Estimated weighted-average fair value per stock option (in dollars per share)   $ 19.58      
Restricted stock | Employees          
Share-based Compensation Arrangement by Share-based Payment Award          
Vesting period (in years)     3 years    
Percentage to vest each year after grant date     33.00%    
Restricted stock | Directors          
Share-based Compensation Arrangement by Share-based Payment Award          
Vesting period (in years)     1 year    
Performance units          
Share-based Compensation Arrangement by Share-based Payment Award          
Vesting period (in years)     3 years    
Performance units | Performance units granted prior to 2023          
Share-based Compensation Arrangement by Share-based Payment Award          
Maximum adjustment to payout ratio     10.00%    
Performance units | Performance units granted prior to 2023 | Minimum          
Share-based Compensation Arrangement by Share-based Payment Award          
Payout ratio (as a percent)     0.00%    
Performance units | Performance units granted prior to 2023 | Maximum          
Share-based Compensation Arrangement by Share-based Payment Award          
Payout ratio (as a percent)     175.00%    
Performance units | Performance units granted in 2023 | Subsequent event          
Share-based Compensation Arrangement by Share-based Payment Award          
Vesting period (in years) 3 years        
Maximum adjustment to payout ratio 25.00%        
Percentage of payout based on total shareholder return 55.00%        
Percentage of payout based on ROE 45.00%        
Performance units | Performance units granted in 2023 | Maximum | Subsequent event          
Share-based Compensation Arrangement by Share-based Payment Award          
Payout ratio (as a percent) 200.00%