Leases (Maturity Analysis of Lease Liabilities and Minimum Payments Due) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Sep. 30, 2019
Maturity Analysis of Operating Lease Liabilities
2020 (excluding the nine months ended 30 June 2020)	$ 20.4
2021	70.6
2022	51.3
2023	43.0
2024	34.9
Thereafter	238.7
Total Undiscounted Lease Payments	458.9
Imputed interest	(65.8)
Present Value of Lease Liability Recognized on the Balance Sheet	$ 393.1
Minimum Payments Due on Operating Leases Prior to Adoption of New Lease Guidance
2020		$ 75.1
2021		62.6
2022		44.4
2023		35.9
2024		28.6
Thereafter		171.4
Total Undiscounted Lease Payments		$ 418.0

Amount of lessee's undiscounted obligation for lease payments for operating lease.

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