New Accounting Guidance (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Oct. 01, 2019
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Lease liabilities	$ 364.6
Right-of-use assets	318.8
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Lease liabilities			$ 375.3
Right-of-use assets			$ 332.3
Other Non-Operating Income (Expense), Net | Accounting Standards Update 2017-12
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Excluded components recognized within earnings	$ 8.9
Interest Expense | Accounting Standards Update 2017-12
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Excluded components recognized within earnings		$ 8.3