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Employee Share-Based Incentive Compensation Plans - Narrative (Details) $ in Millions	3 Months Ended		9 Months Ended		36 Months Ended
	Sep. 30, 2024 USD ($) shares	Sep. 30, 2023 USD ($) shares	Sep. 30, 2024 USD ($) shares	Sep. 30, 2023 USD ($) shares	Dec. 31, 2023 USD ($) shares	Jun. 30, 2024 USD ($)	Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Share-based compensation arrangement by share-based payment award
New grants (in shares)	0	0	11,405	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 | $	$ 28.1		$ 28.1
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 | $	$ 24.3	$ 20.2	$ 24.3	$ 20.2	$ 16.2	$ 28.8	$ 24.3	$ 15.5
Issued (in shares)	0	0	11,405	10,895

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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