Revenue Recognition (Rollforward Of Allowance For Product Returns) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Revenue Recognition [Abstract]
Beginning Balance	$ 20.9	$ 20.3	$ 21.9
Charged to Profit & Loss	33.4	30.3	22.9
Deductions	(34.4)	(31.8)	(25.5)
Other Adjustments	(0.7)	2.1	1.0
Ending Balance	$ 19.2	$ 20.9	$ 20.3