| **Allowance for doubtful accounts (Tables)**   | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
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| **Allowance for Doubtful Accounts [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| Allowance for doubtful accounts                | The activity related to our allowance for doubtful accounts for our retail portfolio, wholesale portfolio, and trade and other receivables is summarized as follows: Three Months Ended April 30, 2012 Three Months Ended April 30, 2011 RetailPortfolio WholesalePortfolio Trade andOtherReceivables Total RetailPortfolio WholesalePortfolio Trade andOtherReceivables Total(in millions)               Allowance for doubtful accounts, at beginning of period$28 $3 $16 $47 $54 $2 $38 $94Provision for doubtful accounts, net of recoveries— (1) 1 — 1 — (3) (2)Charge-off of accounts(A)(2) — — (2) (15) — (1) (16)Allowance for doubtful accounts, at end of period$26 $2 $17 $45 $40 $2 $34 $76 Six Months Ended April 30, 2012 Six Months Ended April 30, 2011 RetailPortfolio WholesalePortfolio Trade andOtherReceivables Total RetailPortfolio WholesalePortfolio Trade andOtherReceivables Total(in millions)               Allowance for doubtful accounts, at beginning of period$31 $3 $16 $50 $58 $2 $36 $96Provision for doubtful accounts, net of recoveries(2) (1) 3 — (1) — (1) (2)Charge-off of accounts(A)(3) — (2) (5) (17) — (1) (18)Allowance for doubtful accounts, at end of period$26 $2 $17 $45 $40 $2 $34 $76_________________________(A)We repossess sold and leased vehicles on defaulted finance receivables and leases, and place them into Inventories. Losses recognized at the time of repossession and charged against the allowance for doubtful accounts were $2 million and $3 million for the three and six months ended April 30, 2012, respectively, and $12 million and $15 million for the three and six months ended April 30, 2011, respectively. |
| Impaired financing receivables                 | Information regarding impaired finance receivables is as follows: As of  April 30, 2012 October 31, 2011 RetailPortfolio WholesalePortfolio Total RetailPortfolio WholesalePortfolio Total(in millions)           Impaired finance receivables with specific loss reserves$16 $— $16 $15 $— $15Impaired finance receivables without specific loss reserves1 — 1 2 — 2Specific loss reserves on impaired finance receivables10 — 10 10 — 10Finance receivables on non-accrual status12 — 12 14 — 14                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| Aging analysis for gross finance receivables   | The Company uses the aging of our receivables as well as other inputs when assessing credit quality. The aging analysis for finance receivables is summarized as follows: As of April 30, 2012 October 31, 2011 RetailPortfolio WholesalePortfolio Total RetailPortfolio WholesalePortfolio Total(in millions)           Current$1,307 $1,281 $2,588 $1,515 $1,328 $2,84330-90 days past due65 2 67 85 5 90Over 90 days past due12 1 13 13 1 14Total finance receivables$1,384 $1,284 $2,668 $1,613 $1,334 $2,947                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |

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The entire disclosure for allowance for credit losses.
+ References
No definition available.
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| - Definition
Tabular disclosure of financing receivables by credit quality indicator. The credit quality indicator is a statistic about the credit quality of financing receivables. Examples include, but not limited to, consumer credit risk scores, credit-rating-agency ratings, an entity's internal credit risk grades, loan-to-value ratios, collateral, collection experience and other internal metrics.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 29 -URI http://asc.fasb.org/extlink&oid=6965416&loc=SL6953659-111524Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 55 -Paragraph 19 -URI http://asc.fasb.org/extlink&oid=6951925&loc=SL6953803-111525
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| - Definition
Tabular disclosure of impaired financing receivables.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=6965416&loc=d3e5212-111524
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