Retirement Plans (Tables)

9 Months Ended

Jun. 30, 2022

Retirement Plans [Abstract]

Summary of Components of Net Pension Income and Summary of Components of Postretirement Benefit Cost

Pension and Postretirement Income / Expense

The following table presents a summary of the components of net pension income (in millions):

	Three Months Ended						Nine Months Ended
	June 30,						June 30,
	2022			2021			2022			2021
Service cost	$	10.7		$	11.2		$	35.9		$	38.3
Interest cost		46.9			47.3			141.6			140.4
Expected return on plan assets		(92.0	)		(92.0	)		(277.0	)		(276.0	)
Amortization of net actuarial loss		2.3			9.8			6.7			25.7
Amortization of prior service cost		2.1			2.3			6.3			6.3
Settlement loss		—			—			0.2			—
Company defined benefit plan income		(30.0	)		(21.4	)		(86.3	)		(65.3	)
Multiemployer and other plans		0.4			0.4			1.1			1.2
Net pension income	$	(29.6	)	$	(21.0	)	$	(85.2	)	$	(64.1	)

The following table presents a summary of the components of the net postretirement cost (in millions):

	Three Months Ended						Nine Months Ended
	June 30,						June 30,
	2022			2021			2022			2021
Service cost	$	0.3		$	0.2		$	0.8		$	0.8
Interest cost		1.7			1.5			4.8			4.4
Amortization of net actuarial loss (gain)		0.4			0.2			(0.4	)		(0.4	)
Amortization of prior service credit		(0.1	)		(0.6	)		(0.5	)		(1.8	)
Net postretirement cost	$	2.3		$	1.3		$	4.7		$	3.0