Pension Benefits and Other Postretirement Benefits (Components of Net Periodic Benefit (Credit) Cost) (Details) - Pension Benefits - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 0.2	$ 0.3
Expected return of plan assets	(0.3)	(0.4)
Amortization of net loss (gain)	0.1	0.1
Net periodic benefit cost (credit)	$ 0.0	$ 0.0