Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (Fair Value, Measurements, Recurring, USD $) In Millions, unless otherwise specified	Mar. 31, 2012		Oct. 01, 2011
Assets
Investments	$ 176		$ 186
Residual Interests	33		40
Liabilities
Total	556		657
Derivative Financial Instruments, Assets | Interest rate
Assets
Derivatives	204	[1]	214	[1]
Liabilities
Derivatives	(21)	[1]
Derivative Financial Instruments, Assets | Foreign exchange
Assets
Derivatives	332	[1]	498	[1]
Liabilities
Derivatives	(177)	[1]
Derivative Financial Instruments, Assets | Other derivatives
Assets
Derivatives	9	[1]
Derivative Financial Instruments, Liabilities | Interest rate
Liabilities
Derivatives			(18)	[1]
Derivative Financial Instruments, Liabilities | Foreign exchange
Liabilities
Derivatives			(262)	[1]
Derivative Financial Instruments, Liabilities | Other derivatives
Liabilities
Derivatives			(1)	[1]
Level 1
Assets
Investments	131		143
Liabilities
Total	131		143
Level 2
Assets
Investments	45		43
Liabilities
Total	392		474
Level 2 | Derivative Financial Instruments, Assets | Interest rate
Assets
Derivatives	204	[1]	214	[1]
Liabilities
Derivatives	(21)	[1]
Level 2 | Derivative Financial Instruments, Assets | Foreign exchange
Assets
Derivatives	332	[1]	498	[1]
Liabilities
Derivatives	(177)	[1]
Level 2 | Derivative Financial Instruments, Assets | Other derivatives
Assets
Derivatives	9	[1]
Level 2 | Derivative Financial Instruments, Liabilities | Interest rate
Liabilities
Derivatives			(18)	[1]
Level 2 | Derivative Financial Instruments, Liabilities | Foreign exchange
Liabilities
Derivatives			(262)	[1]
Level 2 | Derivative Financial Instruments, Liabilities | Other derivatives
Liabilities
Derivatives			(1)	[1]
Level 3
Assets
Residual Interests	33		40
Liabilities
Total	$ 33		$ 40

[1] The Company has a master netting arrangement by counterparty with respect to certain derivative contracts. Contracts in a liability position totaling $122 million and $167 million have been netted against contracts in an asset position in the Condensed Consolidated Balance Sheets at March 31, 2012 and October 1, 2011, respectively.