Other Current Liabilities - Schedule of Other Current Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2019	Sep. 30, 2019
Other current liabilities
Unrealized losses on foreign exchange contracts	$ 7.7	$ 5.4
Product warranty obligations	24.2	25.2
Taxes other than income taxes	50.4	43.8
Accrued interest	28.2	15.5
Income taxes payable	61.3	62.9
Operating lease liabilities	86.8
Other	59.7	75.1
Other current liabilities	$ 318.3	$ 227.9