Discontinued Operations - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	1 Months Ended	12 Months Ended
	Jan. 31, 2012	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 Maximum [Member]	Sep. 30, 2011 Maximum [Member]	Sep. 30, 2013 GAM Notes [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total consideration from sale of business	$ 452
Cash payment, transactions closes	175
Notes receivable received on sale of discontinued operations	277
GAM promissory notes and inventory note, final maturity date	2014-03
Percentage of quarterly cash payments receivable of adjusted EBITDA	50.00%
Minimum payment guaranteed on sale of discontinued operation	11.5
Promissory note included in other asset section			242			214
Company received payment under the GAM Notes		39	23			62
After-tax gain (loss) on the sale of discontinued operations		2	191
Tax benefit on discontinued operations		4
Adjustment of tax effect from gain loss of prior period on discontinued operations		(2)
Settlements net charges			$ 0	$ 1	$ (1)
Period of supply agreement		3 years