Pension and Postretirement Benefits (Tables)

6 Months Ended

Jun. 30, 2024

Postemployment Benefits [Abstract]

Schedule of Components of Net Periodic Cost (Income)

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 June 30,				Six months ended June 30,				Three months ended June 30,				Six months ended June 30,
	2024		2023		2024		2023		2024		2023		2024		2023
Components of net periodic cost (income):
Service cost	$	0.5	$	0.4	$	0.9	$	0.8	$	—	$	—	$	—	$	—
Interest cost	15.3		16.1		30.7		32.1		—		—		—		—
Expected return on plan assets	(19.9)		(20.0)		(39.8)		(39.9)		—		—		—		—
Amortization of prior service cost (credit)	(0.1)		—		(0.1)		—		(0.1)		(0.1)		(0.2)		(0.2)
Amortization of actuarial loss (gain)	(0.3)		(0.6)		(0.6)		(1.2)		—		—		—		—
Net periodic cost (income)	$	(4.5)	$	(4.1)	$	(8.9)	$	(8.2)	$	(0.1)	$	(0.1)	$	(0.2)	$	(0.2)