Leases (Maturity Analysis of Lease Liabilities and Minimum Payments Due) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Sep. 30, 2019
Maturity Analysis of Operating Lease Liabilities
2020 (excluding the three months ended 31 December 2019)	$ 57.5
2021	63.4
2022	45.0
2023	36.1
2024	28.9
Thereafter	179.6
Total Undiscounted Lease Payments	410.5
Imputed interest	(45.9)
Present Value of Lease Liability Recognized on the Balance Sheet	$ 364.6
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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