Goodwill (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Dec. 31, 2009	Dec. 31, 2011	Dec. 31, 2010
Goodwill [Abstract]
Goodwill Beginning Balance, Gross Amount		$ 1,425	$ 1,425
Accumulated Impairment Losses, Beginning Balance		18	18
Goodwill Beginning Balance, Carrying Amount		1,407	1,407
Impairment losses	4
Goodwill Ending Balance, Gross Amount	1,425	1,425	1,425
Accumulated Impairment Losses, Ending Balance	18	18	18
Goodwill Ending Balance, Carrying Amount	$ 1,407	$ 1,407	$ 1,407