Leases (Minimum Lease Payments Expected to be Collected) (Details) - USD ($) $ in Millions	Jun. 30, 2020	Sep. 30, 2019
Minimum Lease Payments Expected to be Collected on Sales-type and Direct Financing Leases
2020 (excluding the nine months ended 30 June 2020)	$ 39.9
2021	155.7
2022	145.2
2023	139.1
2024	133.0
Thereafter	718.2
Total	1,331.1
Unearned interest income	(420.2)
Lease Receivables, net	$ 910.9
Minimum Lease Payments Expected to be Collected Prior to Adoption of New Lease Guidance
2020		$ 162.5
2021		156.9
2022		145.7
2023		139.4
2024		133.2
Thereafter		715.5
Total		1,453.2
Unearned interest income		(472.3)
Lease Receivables, net		$ 980.9