Pension and Postretirement Plans - Schedule of Pension and Postretirement Costs (Benefits) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Pension Plans, Defined Benefit [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	$ 0.0	$ 0.0
Other components of pension and postretirement benefit plans expense:
Interest cost on projected benefit obligation	5.5	3.9
Expected return on plan assets	(5.2)	(7.2)
Amortization of:
Prior service benefit	0.0	0.0
Actuarial gain	(0.1)	0.0
Pension / postretirement cost (benefit)	0.2	(3.3)
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	0.1	0.1
Other components of pension and postretirement benefit plans expense:
Interest cost on projected benefit obligation	1.3	0.7
Expected return on plan assets	0.0	0.0
Amortization of:
Prior service benefit	(0.2)	0.0
Actuarial gain	(0.9)	0.0
Pension / postretirement cost (benefit)	$ 0.3	$ 0.8