| **Finance Receivables - Finance Receivables (Details) - USD ($) $ in Millions**                                                                                                                                                                   | Jul. 31, 2016 | Oct. 31, 2015 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                                                                                                  |               |          |   |
| Loans and Leases Receivable, Gross, Carrying Amount, Covered                                                                                                                                                                                      |               | $ 1,634       | $ 2,021 |
| Less: Allowance for Doubtful accounts                                                                                                                                                                                                             |               | 21            | 26 |
| Total finance receivables, net                                                                                                                                                                                                                    |               | 1,613         | 1,995 |
| Financing Receivable, Recorded Investment, Current                                                                                                                                                                                                | [1]           | 1,410         | 1,779 |
| Finance Receivables, Noncurrent                                                                                                                                                                                                                   |               | 203           | 216 |
| Loans and Leases Receivable, Gross                                                                                                                                                                                                                |               | 1,634         | 2,021 |
| Retail Portfolio [Member]                                                                                                                                                                                                                         |               |          |   |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                                                                                                  |               |          |   |
| Loans and Leases Receivable, Gross, Carrying Amount, Covered                                                                                                                                                                                      |               | 406           | 554 |
| Wholesale Portfolio [Member]                                                                                                                                                                                                                      |               |          |   |
| **Accounts, Notes, Loans and Financing Receivable [Line Items]**                                                                                                                                                                                  |               |          |   |
| Loans and Leases Receivable, Gross, Carrying Amount, Covered                                                                                                                                                                                      |               | $ 1,228       | $ 1,467 |
|                                                                                                                                                                                                                                                   |
| [1]The current portion of finance receivables is computed based on contractual maturities. Actual cash collections typically vary from the contractual cash flows because of prepayments, extensions, delinquencies, credit losses, and renewals. |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Reflects carrying amount of all categories of loans and leases held in portfolio, net of unearned income and the allowance for losses on loans and leases, due from customers, clients, lessees, borrowers, or others more than one year from the balance sheet date (or the normal operating cycle, whichever is longer).
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                |
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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                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Financing receivables that are current.
+ References
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| - Definition
Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Aggregate gross carrying amount of loans and leases receivable covered by loss sharing agreements.
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.
+ References
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| X                                                                                                                                                                                               |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                                  |
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