Financial Instruments and Fair Value Measurements (Schedule of Fair Value of Derivatives, Net of Legal Right to Offset Derivative Settlements) (Detail) (Significant Observable Inputs (Level 2) [Member], USD $) In Millions, unless otherwise specified	Jun. 30, 2013		Sep. 30, 2012
Significant Observable Inputs (Level 2) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Guaranteed investment contract	$ 14	[1]	$ 14	[1]
Derivatives relating to foreign currency	1	[2]
Derivatives relating to interest rates			2	[2]
Total assets at fair value	15		16
Derivatives relating to foreign currency	29	[2]	28	[2]
Hedged long-term debt	35	[3]	36	[3]
Total liabilities at fair value	$ 64		$ 64

[1] Included in "Other assets" in the Consolidated Balance Sheets.

[2] Included in "Prepaid expenses and other current assets" or "Accounts payable and accrued liabilities" in the Consolidated Balance Sheets.

[3] Included in "Current portion of long-term debt" in the Consolidated Balance Sheets.