Pension and Postretirement Benefits - Schedule of Components of Net Periodic (Income) Cost Associated with Pension Plans and Postretirement Benefit Obligations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Plan Disclosure [Line Items]
Net periodic cost (income)	$ 10.6	$ 10.7	$ 11.1
Pension plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	1.6	3.0	5.2
Interest cost	64.6	35.2	27.4
Expected return on plan assets	(80.1)	(79.2)	(83.0)
Amortization of prior service cost (credit)	0.0	0.0	0.0
Amortization of actuarial loss (gain)	(2.4)	0.1	2.3
Net periodic cost (income)	(16.3)	(40.9)	(48.1)
Postretirement benefit obligations
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.0	0.0	0.0
Interest cost	0.0	0.0	0.0
Expected return on plan assets	0.0	0.0	0.0
Amortization of prior service cost (credit)	(0.4)	(0.4)	(0.4)
Amortization of actuarial loss (gain)	0.0	0.0	0.0
Net periodic cost (income)	$ (0.4)	$ (0.4)	$ (0.4)