Allowance for Doubtful Accounts - Impaired Finance Receivables (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Apr. 30, 2013 Retail Portfolio [Member]	Apr. 30, 2012 Retail Portfolio [Member]	Apr. 30, 2013 Impaired finance receivables with specific loss reserves [Member]		Oct. 31, 2012 Impaired finance receivables with specific loss reserves [Member]		Apr. 30, 2013 Impaired finance receivables with specific loss reserves [Member] Retail Portfolio [Member]	Oct. 31, 2012 Impaired finance receivables with specific loss reserves [Member] Retail Portfolio [Member]	Apr. 30, 2013 Impaired finance receivables with specific loss reserves [Member] Wholesale Portfolio [Member]	Oct. 31, 2012 Impaired finance receivables with specific loss reserves [Member] Wholesale Portfolio [Member]	Apr. 30, 2013 Impaired financing receivable without specific loss reserves [Member]	Oct. 31, 2012 Impaired financing receivable without specific loss reserves [Member]	Apr. 30, 2013 Impaired financing receivable without specific loss reserves [Member] Retail Portfolio [Member]	Oct. 31, 2012 Impaired financing receivable without specific loss reserves [Member] Retail Portfolio [Member]	Apr. 30, 2013 Impaired financing receivable without specific loss reserves [Member] Wholesale Portfolio [Member]	Oct. 31, 2012 Impaired financing receivable without specific loss reserves [Member] Wholesale Portfolio [Member]	Apr. 30, 2013 Specific loss reserves on impaired finance receivables [Member]	Oct. 31, 2012 Specific loss reserves on impaired finance receivables [Member]	Apr. 30, 2013 Specific loss reserves on impaired finance receivables [Member] Retail Portfolio [Member]	Oct. 31, 2012 Specific loss reserves on impaired finance receivables [Member] Retail Portfolio [Member]	Apr. 30, 2013 Specific loss reserves on impaired finance receivables [Member] Wholesale Portfolio [Member]	Oct. 31, 2012 Specific loss reserves on impaired finance receivables [Member] Wholesale Portfolio [Member]	Apr. 30, 2013 Finance receivable non-accrual status [Member]	Oct. 31, 2012 Finance receivable non-accrual status [Member]	Apr. 30, 2013 Finance receivable non-accrual status [Member] Retail Portfolio [Member]	Oct. 31, 2012 Finance receivable non-accrual status [Member] Retail Portfolio [Member]	Apr. 30, 2013 Finance receivable non-accrual status [Member] Wholesale Portfolio [Member]	Oct. 31, 2012 Finance receivable non-accrual status [Member] Wholesale Portfolio [Member]
Finance Receivable, Impaired [Line Items]
Impaired Financing Receivable, Average Recorded Investment	$ 13	$ 17
Impaired Financing Receivable, Recorded Investment			12	[1]	14	[1]	12	14	0	0	1	1	1	1	0	0
Specific loss reserves on impaired finance receivables																	7	9	7	9	0	0
Finance receivables on non-accrual status																							$ 9	$ 10	$ 9	$ 10	$ 0	$ 0

[1] Certain impaired finance receivables are measured at fair value on a nonrecurring basis. An impairment charge is recorded for the amount by which the carrying value of the receivables exceeds the fair value of the underlying collateral, net of remarketing costs. Fair values of the underlying collateral are determined by reference to dealer vehicle value publications adjusted for certain market factors.