Retirement Benefits (Tables)

6 Months Ended

Mar. 31, 2021

Retirement Benefits [Abstract]

Schedule of Net Periodic Benefit Cost

The components of net periodic (benefit) cost for our defined benefit pension plans for the three and six months ended 31 March 2021 and 2020 were as follows:

	Pension Benefits
	2021		2020
Three Months Ended 31 March	U.S.	International	U.S.	International
Service cost	$5.3	$5.9	$5.8	$5.8
Interest cost	17.3	6.3	22.8	6.2
Expected return on plan assets	(48.7)	(21.0)	(47.2)	(19.4)
Prior service cost amortization	0.3	—	0.3	—
Actuarial loss amortization	19.6	4.8	21.0	4.9
Settlements	—	—	1.5	—
Other	—	0.2	—	0.2
Net Periodic (Benefit) Cost	($6.2)	($3.8)	$4.2	($2.3)

	Pension Benefits
	2021		2020
Six Months Ended 31 March	U.S.	International	U.S.	International
Service cost	$10.7	$11.6	$11.6	$11.7
Interest cost	34.5	12.4	45.6	12.4
Expected return on plan assets	(97.3)	(41.2)	(94.4)	(38.9)
Prior service cost amortization	0.6	—	0.6	—
Actuarial loss amortization	39.3	9.4	42.0	9.8
Settlements	—	—	1.5	—
Other	—	0.5	—	0.4
Net Periodic (Benefit) Cost	($12.2)	($7.3)	$6.9	($4.6)