Leases (Summary of Lease Information) (Details) - USD ($) $ in Millions		12 Months Ended
		Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2023
Lessee, Lease, Description [Line Items]
Lease right-of-use asset		$ 73.2	$ 85.4
Right of use asset - financial statement location		Other assets	Other assets
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]		Other current liabilities	Other current liabilities
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]		Other Liabilities	Other Liabilities
Operating Lease, Liability, Current		$ 15.4	$ 16.7
Lease liability		$ 72.5	$ 86.5
Leases, weighted average remaining term (years)		8 years 1 month 6 days	8 years 1 month 6 days
Leases, weighted average incremental borrowing rate (percent)		9.10%	8.80%
Lease expense	[1]	$ 23.9	$ 18.0	$ 12.5
Leased assets obtained in exchange for new lease liabilities		2.2	32.1	25.9
Cash paid for amounts included in the measurement of lease liabilities		22.8	17.5	$ 12.2
Operating Lease, Liability, Noncurrent		$ 57.1	$ 69.8

[1] Lease expense is included in Cost of products sold or SG&A expense based on the nature of the lease. Short-term lease expense and variable lease expense are excluded from this amount and are not material.