Retirement Benefits (Tables)

9 Months Ended

Jun. 30, 2021

Retirement Benefits [Abstract]

Schedule of Net Benefit Costs

The components of net periodic benefit cost are (in millions):

	Pension Benefits
	Three Months Ended June 30,				Nine Months Ended June 30,
	2021		2020		2021		2020
Service cost	$	23.1	$	22.6	$	68.7	$	68.2
Interest cost	31.5		34.0		94.3		102.3
Expected return on plan assets	(60.9)		(60.9)		(182.0)		(183.3)
Amortization:
Prior service cost	0.3		0.2		1.0		0.7
Net actuarial loss	37.0		36.7		110.5		110.3
Settlements	27.2		(0.8)		26.8		(2.3)
Net periodic benefit cost	$	58.2	$	31.8	$	119.3	$	95.9

	Other Postretirement Benefits
	Three Months Ended June 30,				Nine Months Ended June 30,
	2021		2020		2021		2020
Service cost	$	0.3	$	0.3	$	0.8	$	0.8
Interest cost	0.3		0.4		0.9		1.2
Amortization:
Prior service credit	(1.4)		(1.4)		(4.1)		(4.1)
Net actuarial loss	0.3		0.4		0.9		1.1
Net periodic benefit credit	$	(0.5)	$	(0.3)	$	(1.5)	$	(1.0)