Significant Accounting Policies (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Trade Accounts Receivable and Accounts Receivable, Other
Allowance for Doubtful Accounts	$ 1.7	$ 1.8
Selling, general and administrative expenses
Property Plant and Equipment
Depreciation expense	$ 96.1	$ 97.2	$ 99.2