Revenue Recognition - Schedule of Contract Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2020	Sep. 30, 2019
Contract With Customer Liability [Abstract]
Customer advances	$ 491.4	$ 382.0
Other current liabilities	59.5	78.2
Other long-term liabilities	53.7	52.3
Total contract liabilities	$ 604.6	$ 512.5