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Employee Share-Based Incentive Compensation Plans - Narrative (Details) $ in Millions	12 Months Ended			36 Months Ended
	Dec. 31, 2023 USD ($) shares	Dec. 31, 2022 USD ($) shares	Dec. 31, 2021 USD ($) shares	Dec. 31, 2021 USD ($) shares	Dec. 31, 2020 USD ($)
Share-based compensation arrangement by share-based payment award
Grants in period (in shares)	10,895	13,225	13,475
Performance Shares
Share-based compensation arrangement by share-based payment award
Vesting period	3 years
Performance cycle period	3 years
New grants (in shares)				750
Additional compensation cost that would be recognized if all outstanding performance shares vested \| $	$ 27.9
Performance Shares \| 2023 – 2025
Share-based compensation arrangement by share-based payment award
Targeted performance goal (as a percent)	11.00%
Payout maximum growth target percentage	200.00%
Performance Shares \| 2022 – 2024
Share-based compensation arrangement by share-based payment award
Targeted performance goal (as a percent)	9.00%
Payout maximum growth target percentage	200.00%
Performance Shares \| 2023 – 2025
Share-based compensation arrangement by share-based payment award
Targeted performance goal (as a percent)	8.00%
Payout maximum growth target percentage	200.00%
Performance Shares \| Minimum
Share-based compensation arrangement by share-based payment award
Share-based compensation arrangement by share-based payment award, multiplier	0
Performance Shares \| Minimum \| 2023 – 2025
Share-based compensation arrangement by share-based payment award
Payout range for growth target percentage	6.00%
Performance Shares \| Minimum \| 2022 – 2024
Share-based compensation arrangement by share-based payment award
Payout range for growth target percentage	4.00%
Performance Shares \| Minimum \| 2023 – 2025
Share-based compensation arrangement by share-based payment award
Payout range for growth target percentage	3.00%
Performance Shares \| Maximum
Share-based compensation arrangement by share-based payment award
Share-based compensation arrangement by share-based payment award, multiplier	2
Performance Shares \| Maximum \| 2023 – 2025
Share-based compensation arrangement by share-based payment award
Payout range for growth target percentage	16.00%
Performance Shares \| Maximum \| 2022 – 2024
Share-based compensation arrangement by share-based payment award
Payout range for growth target percentage	14.00%
Performance Shares \| Maximum \| 2023 – 2025
Share-based compensation arrangement by share-based payment award
Payout range for growth target percentage	13.00%
Restricted Stock
Share-based compensation arrangement by share-based payment award
Vesting period	34 months
Additional compensation cost that would be recognized if all outstanding performance shares vested \| $	$ 16.2	$ 15.5	$ 15.9	$ 15.9	$ 15.2
Issued (in shares)	10,895	13,225	13,475