Other Long-Term Assets (Details) - USD ($) $ in Millions	Sep. 30, 2020	Sep. 30, 2019
Other Assets Noncurrent Disclosure [Abstract]
Lease right of use asset (See Note 12 of Notes to Consolidated Financial Statements)	$ 162.2
Deferred income taxes, net (See Note 6 of Notes to Consolidated Financial Statements)	78.6	$ 107.9
Rabbi trust, less current portion	17.9	20.0
Investments in unconsolidated affiliates	12.6	11.0
Customer finance receivables	5.6	7.2
Other	10.1	10.7
Other long-term assets, gross	287.0	156.8
Less allowance for doubtful receivables	(0.5)	(0.4)
Other long-term assets, net	$ 286.5	$ 156.4