| **Summary of Significant Accounting Policies - Variable Interest Entities (Details) - USD ($) $ in Millions**                        | May 28, 2015 | Jul. 31, 2016 | Oct. 31, 2015 | Jul. 31, 2015 | Oct. 31, 2014 |
|--------------------------------------------------------------------------------------------------------------------------------------|--------------|---------------|---------------|---------------|---------------|
| **Variable Interest Entity [Line Items]**                                                                                            |         |          |          |          |          |
| Cash and cash equivalents                                                                                                            |         | $ 547         | $ 912         | $ 547         | $ 497         |
| Variable Interest Entity Primary Beneficiary, Blue Diamond Parts [Member]                                                            |         |          |          |          |          |
| **Variable Interest Entity [Line Items]**                                                                                            |         |          |          |          |          |
| Variable Interest Entity, Consolidated, Carrying Amount, Assets                                                                      |         | 40            | 50            |          |          |
| Cash and cash equivalents                                                                                                            |         | 3             | 7             |          |          |
| Variable Interest Entity, Consolidated, Carrying Amount, Liabilities                                                                 |         | 12            | 7             |          |          |
| Variable Interest Entity Primary Beneficiary, Blue Diamond Trucks [Member]                                                           |         |          |          |          |          |
| **Variable Interest Entity [Line Items]**                                                                                            |         |          |          |          |          |
| Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners                                                               | 25.00%       |          |          |          |          |
| Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests                                                          | $ 27         |          |          |          |          |
| 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                                                                 |         | 850           | 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                                                                      |         | 178           | 235           |          |          |
| Variable Interest Entity, Consolidated, Carrying Amount, Liabilities                                                                 |         | $ 118         | $ 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
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| - Definition
Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests).
+ References
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| - Definition
The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.
+ References
No definition available.
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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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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The carrying amount of the consolidated Variable Interest Entity's liabilities included in the reporting entity's statement of financial position.
+ References
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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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| X                                                                                                                                                                   |
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