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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, 2025 USD ($) shares	Sep. 30, 2024 USD ($) shares	Sep. 30, 2025 USD ($) shares	Sep. 30, 2024 USD ($) shares	Dec. 31, 2024 USD ($) shares	Dec. 31, 2023 USD ($) shares	Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($)
Share-based compensation arrangement by share-based payment award
New grants (in shares)	25	0	10,670	11,405
Performance Share
Share-based compensation arrangement by share-based payment award
Vesting period			3 years
Performance cycle period			3 years
New grants (in shares)					30	100
Additional compensation cost that would be recognized if all outstanding performance shares vested \| $	$ 37.6		$ 37.6
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 \| $	$ 25.9	$ 24.3	$ 25.9	$ 24.3	$ 19.9	$ 16.2	$ 30.7	$ 28.8
Issued (in shares)	25	0	10,670	11,405