Pension and Other Benefits - Net Pension and Other Benefit Costs (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0.1	$ 0.2
Interest cost	8.7	6.3
Expected return on plan assets	(7.0)	(8.2)
Amortization of prior service cost	0.1	0.1
Amortization of actuarial losses (gains)	2.6	2.6
Settlement losses	0.0	0.0
NET PERIODIC BENEFIT COST	4.5	1.0
Other Benefits
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.0	0.0
Interest cost	0.2	0.1
Expected return on plan assets	0.0	0.0
Amortization of prior service cost	0.0	0.0
Amortization of actuarial losses (gains)	(0.1)	(0.1)
Settlement losses	0.0	0.0
NET PERIODIC BENEFIT COST	$ 0.1	$ 0.0