Other Current Liabilities - Schedule of Other Current Liabilities (Details) - USD ($) $ in Millions	Jun. 30, 2020	Sep. 30, 2019
Other current liabilities
Unrealized losses on foreign exchange contracts	$ 21.9	$ 5.4
Product warranty obligations	21.5	25.2
Taxes other than income taxes	57.1	43.8
Accrued interest	30.4	15.5
Dividends payable	118.3	0.0
Income taxes payable	36.6	62.9
Operating lease liabilities	89.2
Other	76.3	75.1
Other current liabilities	$ 451.3	$ 227.9