Leases (Maturity Analysis of Lease Liabilities and Minimum Payments Due) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Sep. 30, 2019
Maturity Analysis of Operating Lease Liabilities
2020 (excluding the six months ended 31 March 2020)	$ 39.2
2021	66.4
2022	48.3
2023	40.6
2024	33.2
Thereafter	232.0
Total Undiscounted Lease Payments	459.7
Imputed interest	(66.3)
Present Value of Lease Liability Recognized on the Balance Sheet	$ 393.4
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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