Goodwill and Other Intangible Assets (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2011
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill held for sale	$ 74	$ 74
Goodwill impairment loss	430	430	0
Amortization of other intangible assets		75	56	53
Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract]
Future amortization expense, 2014	73	73
Future amortization expense, 2015	73	73
Future amortization expense, 2016	67	67
Future amortization expense, 2017	62	62
Future amortization expense, 2018	$ 57	$ 57