Derivatives (Schedule Of Fair Value Of Outstanding Derivative Instruments) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Sep. 30, 2018
Derivatives, Fair Value [Line Items]
Derivative assets	$ 7.9	$ 8.9
Derivative liabilities	1.0	0.8
Commodity Swaps [Member] | Other Receivables [Member] | Designated as Hedging [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	0.2
Commodity Swaps [Member] | Accounts Payable [Member] | Designated as Hedging [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities	0.1	0.4
Interest Rate Swaps [Member] | Other Receivables [Member] | Designated as Hedging [Member]
Derivatives, Fair Value [Line Items]
Derivative assets		1.8
Interest Rate Swaps [Member] | Deferred Charges And Other [Member] | Designated as Hedging [Member]
Derivatives, Fair Value [Line Items]
Derivative assets		1.0
Interest Rate Swaps [Member] | Accrued Interest [Member] | Designated as Hedging [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities		(0.3)
Foreign Exchange Contracts [Member] | Other Receivables [Member] | Designated as Hedging [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	6.2	5.5
Foreign Exchange Contracts [Member] | Other Receivables [Member] | Not Designated as Hedging [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	1.3	0.4
Foreign Exchange Contracts [Member] | Deferred Charges And Other [Member] | Designated as Hedging [Member]
Derivatives, Fair Value [Line Items]
Derivative assets	0.2	0.2
Foreign Exchange Contracts [Member] | Accounts Payable [Member] | Designated as Hedging [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities	0.2	0.3
Foreign Exchange Contracts [Member] | Accounts Payable [Member] | Not Designated as Hedging [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities	$ 0.7	0.2
Foreign Exchange Contracts [Member] | Other Long-term Liabilities [Member] | Designated as Hedging [Member]
Derivatives, Fair Value [Line Items]
Derivative liabilities		$ 0.2