| **Fair Value Measurements - Financial Instruments Measured on Nonrecurring Basis (Details) - USD ($) $ in Millions**                                                                                                                                                                                                                                                                                                     | Jul. 31, 2016 | Oct. 31, 2015 |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| Impaired finance receivables with specific loss reserves [Member]                                                                                                                                                                                                                                                                                                                                                        |               |          |   |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                                                                                                                                                                                                                                                                                                                         |               |          |   |
| Impaired Financing Receivable, Recorded Investment                                                                                                                                                                                                                                                                                                                                                                       |               | $ 18          | $ 21 |
| Impaired finance receivables with specific loss reserves [Member] | Fair Value, Inputs, Level 2 [Member]                                                                                                                                                                                                                                                                                                                 |               |          |   |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                                                                                                                                                                                                                                                                                                                         |               |          |   |
| Impaired Financing Receivable, Recorded Investment                                                                                                                                                                                                                                                                                                                                                                       | [1]           | 18            | 21 |
| Specific loss reserves on impaired finance receivables [Member]                                                                                                                                                                                                                                                                                                                                                          |               |          |   |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                                                                                                                                                                                                                                                                                                                         |               |          |   |
| Specific loss reserve                                                                                                                                                                                                                                                                                                                                                                                                    |               | (9)           | (9) |
| Specific loss reserves on impaired finance receivables [Member] | Fair Value, Inputs, Level 2 [Member]                                                                                                                                                                                                                                                                                                                   |               |          |   |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                                                                                                                                                                                                                                                                                                                         |               |          |   |
| Specific loss reserve                                                                                                                                                                                                                                                                                                                                                                                                    |               | (9)           | (9) |
| Estimate of Fair Value Measurement [Member] | Fair Value, Measurements, Nonrecurring [Member] | Fair Value, Inputs, Level 2 [Member]                                                                                                                                                                                                                                                                                     |               |          |   |
| **Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]**                                                                                                                                                                                                                                                                                                                         |               |          |   |
| Finance Receivables Fair Value Disclosure                                                                                                                                                                                                                                                                                                                                                                                |               | $ 9           | $ 12 |
|                                                                                                                                                                                                                                                                                                                                                                                                                          |
| [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. |

| X                                                                                                                                                                                                                                                                  |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Finance Receivables Fair Value Disclosure
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 14A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of allowance for credit losses related to recorded investment.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Recorded Investment -URI http://asc.fasb.org/extlink&oid=65880944Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524
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| X                                                                                                                                                                                                                                  |
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