Retirement Benefits (Tables)

9 Months Ended

Jun. 30, 2025

Retirement Benefits [Abstract]

Schedule of Net Periodic (Benefit) Cost

The components of net periodic cost for our defined benefit pension plans for the three and nine months ended 30 June 2025 and 2024 were as follows:

	Pension Benefits
	2025			2024
Three Months Ended 30 June	U.S.	International	Total	U.S.	International	Total
Service cost	$2.3	$3.0	$5.3	$2.4	$2.8	$5.2
Non-service cost:
Interest cost	29.9	14.5	44.4	33.7	14.9	48.6
Expected return on plan assets	(33.1)	(15.3)	(48.4)	(30.0)	(11.7)	(41.7)
Prior service cost amortization	0.2	0.3	0.5	0.3	0.2	0.5
Actuarial loss amortization	11.7	2.4	14.1	14.3	3.2	17.5
Settlements	—	0.3	0.3	—	0.4	0.4
Other	—	0.1	0.1	—	0.6	0.6
Net Periodic Cost	$11.0	$5.3	$16.3	$20.7	$10.4	$31.1

	Pension Benefits
	2025			2024
Nine Months Ended 30 June	U.S.	International	Total	U.S.	International	Total
Service cost	$6.9	$8.6	$15.5	$7.2	$8.4	$15.6
Non-service cost:
Interest cost	89.7	42.2	131.9	101.1	44.7	145.8
Expected return on plan assets	(99.5)	(44.5)	(144.0)	(90.0)	(35.2)	(125.2)
Prior service cost amortization	0.8	0.7	1.5	0.9	0.7	1.6
Actuarial loss amortization	35.1	7.2	42.3	42.9	9.6	52.5
Settlements	—	0.4	0.4	—	0.6	0.6
Other	—	0.2	0.2	—	0.8	0.8
Net Periodic Cost	$33.0	$14.8	$47.8	$62.1	$29.6	$91.7