Employees - Financial Information Related to Pension Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Change in projected benefit obligation:
Benefit obligation at beginning of year	$ 106.7	$ 105.3
Interest cost	5.0	5.3	$ 3.7
Actuarial loss (gain)	(6.7)	2.0
Benefits paid	(6.0)	(5.9)
Other (effect of curtailment/settlement)	(0.1)	0.0
Projected benefit obligations at end of year	98.9	106.7	105.3
Change in plan assets:
Fair value of plan assets at beginning of year	104.2	102.2
Actual gain (loss) on plan assets	(0.7)	7.9
Employer contribution	0.1	0.0
Benefits paid	(6.0)	(5.9)
Other (effect of curtailment/settlement)	(0.1)	0.0
Fair value of plan assets at end of year	97.5	104.2	$ 102.2
Under-funded status at end of year	$ (1.4)	$ (2.5)