Goodwill And Other Intangible Assets (Narrative) (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Mar. 31, 2012 Y	Sep. 30, 2011
Goodwill And Other Intangible Assets [Line Items]
Finite-lived intangible assets	$ 3	$ 3
Useful life of intangible assets, minimum (in years)	6
Useful life of intangible assets, maximum (in years)	14
Weighted average useful life of intangible assets (in years)	12
Maximum [Member]
Goodwill And Other Intangible Assets [Line Items]
Amortization of intangible assets, year one	1
Amortization of intangible assets, year two	1
Amortization of intangible assets, year three	1
Amortization of intangible assets, year four	1
Amortization of intangible assets, year five	$ 1