Summary of Significant Accounting Policies Stock-Based Compensation (Details) - $ / shares	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	May 06, 2021
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)	257,780	437,269	530,612
Estimated weighted-average fair value per stock option (in dollars per share)	$ 19.58	$ 14.71	$ 13.20
Risk-free interest rate, minimum (as a percent)	3.80%	0.20%	0.10%
Risk-free interest rate, maximum (as a percent)	4.80%	1.60%	0.90%
Dividend yield (as a percent)	3.20%	3.20%	2.90%
Expected volatility (as a percent)	22.00%	21.00%	21.00%
Expected life (in years)	8 years 3 months 18 days	8 years 8 months 12 days	8 years 8 months 12 days
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 after January 1, 2023
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 after January 1, 2023 | Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Payout ratio (as a percent)	200.00%