Pension and Postretirement Benefits (Tables)

9 Months Ended

Sep. 30, 2023

Postemployment Benefits [Abstract]

Schedule of Components of Net Periodic (Income) Cost Associated with Pension Plans and Postretirement Benefit Obligations

The following table sets forth the components of the net periodic cost (income) associated with our pension plans and our postretirement benefit obligations:

	Pension plans								Postretirement benefit obligations
	Three months ended September 30,				Nine months ended September 30,				Three months ended September 30,				Nine months ended September 30,
	2023		2022		2023		2022		2023		2022		2023		2022
Components of net periodic cost (income):
Service cost	$	0.4	$	0.7	$	1.2	$	2.3	$	—	$	—	$	—	$	—
Interest cost	16.3		8.8		48.4		26.4		—		—		—		—
Expected return on plan assets	(20.2)		(19.6)		(60.1)		(59.4)		—		—		—		—
Amortization of prior service cost (credit)	—		—		—		—		(0.1)		(0.1)		(0.3)		(0.3)
Amortization of actuarial loss (gain)	(0.6)		—		(1.8)		—		—		—		—		—
Net periodic cost (income)	$	(4.1)	$	(10.1)	$	(12.3)	$	(30.7)	$	(0.1)	$	(0.1)	$	(0.3)	$	(0.3)