Summary of Significant Accounting Policies (Schedule of Reserves for Excess and Obsolete Inventory) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of year	$ 7.5	$ 5.1	$ 4.4
Provision charged to expense	(4.7)	(3.4)	(2.2)
Inventory disposed	(0.7)	(1.2)	(1.2)
SEC Schedule, 12-09, Valuation Allowances and Reserves, Increase (Decrease) Adjustment	0.2	0.2	(0.3)
Balance at end of year	$ 11.7	$ 7.5	$ 5.1