Fair Value Measurements (Assets And Liabilities Measured At Fair Value On Recurring Basis) (Details) (USD $) In Millions	Jun. 30, 2011	Sep. 30, 2010
Total derivative assets	$ 39.7	$ 48.9
Deferred compensation investment	26.1	22.2
Total derivative liabilities	46.8	33.8
Deferred compensation liabilities	40.6	31.2
Derivative Assets [Member]
Total derivative assets	2.9	16.7
Derivative Assets [Member] | Fair Value, Inputs, Level 2 [Member]
Total derivative assets	2.9	16.7
Fair Value, Inputs, Level 1 [Member]
Total derivative assets	36.8	32.2
Deferred compensation investment	26.1	22.2
Fair Value, Inputs, Level 1 [Member] | Marketable securities [Member]
Total derivative assets	10.7	10.0
Fair Value, Inputs, Level 2 [Member]
Total derivative assets	2.9	16.7
Total derivative liabilities	46.8	33.8
Deferred compensation liabilities	40.6	31.2
Fair Value, Inputs, Level 2 [Member] | Derivative Liabilities [Member]
Total derivative liabilities	16.6	2.6
Marketable securities [Member]
Total derivative assets	10.7	10.0
Derivative Liabilities [Member]
Total derivative liabilities	$ 16.6	$ 2.6