Retirement Benefits (Tables)

3 Months Ended

Dec. 31, 2023

Retirement Benefits [Abstract]

Schedule of Net Benefit Costs

The components of net periodic pension and postretirement benefit cost (credit) were (in millions):

	Pension Benefits
	Three Months Ended December 31,
	2023		2022
Service cost	$	9.3	$	10.6
Interest cost	36.6		39.2
Expected return on plan assets	(42.2)		(51.3)
Amortization of net actuarial gain	(0.3)		(1.0)
Net periodic pension benefit cost (credit)	$	3.4	$	(2.5)

	Other Postretirement Benefits
	Three Months Ended December 31,
	2023		2022
Service cost	$	0.1	$	0.1
Interest cost	0.6		0.6
Amortization of net actuarial loss	0.4		0.1
Net periodic postretirement benefit cost	$	1.1	$	0.8