Retirement Benefits (Tables)

9 Months Ended

Jun. 30, 2020

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,
	2020			2019			2020			2019
Service cost	$	22.6		$	19.6		$	68.2		$	58.7
Interest cost	34.0			39.6			102.3			118.8
Expected return on plan assets	(60.9		)	(61.2		)	(183.3		)	(183.6		)
Amortization:
Prior service cost	0.2			0.3			0.7			0.9
Net actuarial loss	36.7			19.4			110.3			58.4
Settlements	(0.8		)	(0.2		)	(2.3		)	(0.6		)
Net periodic benefit cost	$	31.8		$	17.5		$	95.9		$	52.6

	Other Postretirement Benefits
	Three Months Ended June 30,						Nine Months Ended June 30,
	2020			2019			2020			2019
Service cost	$	0.3		$	0.2		$	0.8		$	0.7
Interest cost	0.4			0.7			1.2			1.8
Amortization:
Prior service credit	(1.4		)	(1.4		)	(4.1		)	(4.1		)
Net actuarial loss	0.4			0.2			1.1			0.6
Net periodic benefit credit	$	(0.3	)	$	(0.3	)	$	(1.0	)	$	(1.0	)