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Employee Share-Based Incentive Compensation Plans - Narrative (Details) $ in Millions	3 Months Ended		36 Months Ended
	Mar. 31, 2024 USD ($) shares	Mar. 31, 2023 USD ($) shares	Dec. 31, 2023 USD ($) shares	Dec. 31, 2022 USD ($)
Share-based compensation arrangement by share-based payment award
New grants (in shares)	10,405	10,895
Performance Share
Share-based compensation arrangement by share-based payment award
Vesting period	3 years
Performance cycle period	3 years
New grants (in shares)			100
Additional compensation cost that would be recognized if all outstanding performance shares vested \| $	$ 45.2
Performance Share \| Minimum
Share-based compensation arrangement by share-based payment award
Share-based compensation arrangement by share-based payment award, multiplier	0
Performance Share \| Maximum
Share-based compensation arrangement by share-based payment award
Share-based compensation arrangement by share-based payment award, multiplier	2
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 \| $	$ 31.3	$ 28.3	$ 16.2	$ 15.5
Issued (in shares)	10,405	10,895