Fair Value Measurements (Level 3 Reconciliation) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended	9 Months Ended
	Jul. 31, 2012		Jul. 31, 2011		Apr. 30, 2011	Jul. 31, 2012		Jul. 31, 2011
Guarantees [Member]
Fair Value Assets And Liablities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	$ 0	[1]	$ 0	[1]		$ 0		$ 0
Balance at beginning of period	7		0		0	6		0
Transfers Into Level 3						0		0
Transfers out of Level 3						0		0
Issuance						1		0
Settlements	0		0			0		0
Balance at end of period	7		0		0	7		0
Fair Value Change in Unrealized Gains on Assets and Liabilities Still Held	0		0		0	0
Retained Interest [Member]
Fair Value Assets And Liablities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0	[1]	0	[1]		0	[1]	1
Balance at beginning of period	0		0		53	0		53
Transfers Into Level 3						0		0
Transfers out of Level 3						0		0
Issuance						0		0
Settlements	0		0			0		(54)
Balance at end of period	0		0		0	0		0
Fair Value Change in Unrealized Gains on Assets and Liabilities Still Held	0		0		0	0
Commodity Contract [Member]
Fair Value Assets And Liablities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0	[1]	(1)	[1]		(1)		5
Balance at beginning of period	0		6		2	(2)		2
Transfers Into Level 3						0		0
Transfers out of Level 3						2		0
Issuance						0		0
Settlements	0		(3)			1		(5)
Balance at end of period	0		2		6	0		2
Fair Value Change in Unrealized Gains on Assets and Liabilities Still Held	$ 0		$ 2		$ 2	$ 0

[1] For commodity contracts, gains (losses) are included in Costs of products sold. For retained interests, gains recognized are included in Finance revenues.