| **Summary of Significant Accounting Policies - Variable Interest Entities (Details) - USD ($) $ in Millions**                        | Apr. 30, 2016 | Oct. 31, 2015 | Apr. 30, 2015 | Oct. 31, 2014 |
|--------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|---------------|---------------|
| **Variable Interest Entity [Line Items]**                                                                                            |          |          |          |          |
| Cash and cash equivalents                                                                                                            | $ 589         | $ 912         | $ 583         | $ 497         |
| Variable Interest Entity Primary Beneficiary, Blue Diamond Parts [Member]                                                            |          |          |          |          |
| **Variable Interest Entity [Line Items]**                                                                                            |          |          |          |          |
| Variable Interest Entity, Consolidated, Carrying Amount, Assets                                                                      | 49            | 50            |          |          |
| Cash and cash equivalents                                                                                                            | 2             | 7             |          |          |
| Variable Interest Entity, Consolidated, Carrying Amount, Liabilities                                                                 | 9             | 7             |          |          |
| Variable Interest Entity Primary Beneficiary Securitizations Treated As Borrowings [Member] | Financial Services Operations [Member] |          |          |          |          |
| **Variable Interest Entity [Line Items]**                                                                                            |          |          |          |          |
| Variable Interest Entity, Consolidated, Carrying Amount, Assets                                                                      | 1,000         | 1,100         |          |          |
| Variable Interest Entity, Consolidated, Carrying Amount, Liabilities                                                                 | 870           | 844           |          |          |
| Transaction Does Not Qualify for Sale Accounting [Member] | Financial Services Operations [Member]                                   |          |          |          |          |
| **Variable Interest Entity [Line Items]**                                                                                            |          |          |          |          |
| Variable Interest Entity, Consolidated, Carrying Amount, Assets                                                                      | 277           | 235           |          |          |
| Variable Interest Entity, Consolidated, Carrying Amount, Liabilities                                                                 | $ 171         | $ 107         |          |          |

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| - Definition
Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash -URI http://asc.fasb.org/extlink&oid=6506951Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6676-107765Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3044-108585Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash Equivalents -URI http://asc.fasb.org/extlink&oid=6507016Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682
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| - Definition
The carrying amount of the consolidated Variable Interest Entity's assets included in the reporting entity's statement of financial position.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (bb) -URI http://asc.fasb.org/extlink&oid=64801991&loc=d3e5710-111685
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| - 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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