Derivatives - Schedule of Derivative Instruments in Statement of Financial Position, Fair Value (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013		Sep. 30, 2012
Derivatives, Fair Value [Line Items]
Total Asset Derivatives			$ 3
Total Liability Derivatives			29
Designated as Hedging Instrument [Member] | Accounts Payable and Accrued Liabilities [Member] | Interest Rate [Member]
Derivatives, Fair Value [Line Items]
Total Asset Derivatives		[1]	2	[1]
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Total Liability Derivatives			29
Not Designated as Hedging Instrument [Member] | Prepaid Expenses and Other Current Assets [Member] | Other [Member]
Derivatives, Fair Value [Line Items]
Total Asset Derivatives		[2]	1	[2]
Total Liability Derivatives		[2]	1	[2]
Not Designated as Hedging Instrument [Member] | Accounts Payable and Accrued Liabilities, and Other Liabilities [Member] | Foreign Currency [Member]
Derivatives, Fair Value [Line Items]
Total Liability Derivatives		[1]	$ 28	[1]

[1] Contracts of $2 million presented on a gross basis in this table at September 30, 2012 have the legal right to offset against other types of contracts with a common counterparty and, therefore, are presented on a net basis in "Accounts payable and accrued liabilities" in the Consolidated Balance Sheet.

[2] Contracts in fiscal 2012 an asset and liability position presented on a gross basis in this table have the legal right of offset and, therefore, are presented on a net basis in "Prepaid expenses and other current assets" in the Consolidated Balance Sheets.