Employee Benefit Plans (Components of Net Periodic Benefit Cost) (Details) - Pension Benefits [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Components of net periodic benefit cost
Service cost	$ 2.1	$ 3.8	$ 6.1
Interest cost	8.9	6.2	5.1
Expected return on plan assets	(9.4)	(9.1)	(8.6)
Amortization of prior service cost	0.1	0.1	0.2
Amortization of net loss	1.1	5.3	7.7
Settlements or curtailments	0.8	(0.2)	1.2
Other	(0.4)	(0.1)	(0.4)
Total net periodic benefit cost	$ 3.2	$ 6.0	$ 11.3