| **Fair value measurements**            | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               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| **Fair value measurements [Abstract]** | Â                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       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| Fair value measurements                | Fair value measurementsFor assets and liabilities measured at fair value on a recurring and nonrecurring basis, a three-level hierarchy of measurements based upon the reliability of observable and unobservable inputs is used to arrive at fair value. Observable inputs are independent market data, while unobservable inputs reflect our assumptions about valuation. Depending on the inputs, we classify each fair value measurement as follows:•Level 1—based upon quoted prices for identical instruments in active markets,•Level 2—based upon quoted prices for similar instruments, prices for identical or similar instruments in markets that are not active, or model-derived valuations all of whose significant inputs are observable, and•Level 3—based upon one or more significant unobservable inputs.The following section describes key inputs and assumptions in our valuation methodologies:Cash Equivalents and Restricted Cash Equivalents. We classify highly liquid investments, with a maturity of 90 days or less at the date of purchase, including U.S. Treasury bills, federal agency securities, and commercial paper, as cash equivalents. We use quoted prices where available and use a matrix of observable market-based inputs when quoted prices are unavailable.Marketable Securities. Our marketable securities portfolios are classified as available-for-sale and primarily include investments in U.S. government and commercial paper with a maturity of greater than 90 days at the date of purchase. We use quoted prices from active markets to determine their fair values.Derivative Assets and Liabilities. We measure the fair value of derivatives assuming that the unit of account is an individual derivative transaction and that each derivative could be sold or transferred on a stand-alone basis. We classify within Level 2 our derivatives that are traded over-the-counter and valued using internal models based on observable market inputs. In certain cases, market data is not available and we estimate inputs such as in situations where trading in a particular commodity is not active. Measurements based upon these unobservable assumptions are classified within Level 3. For more information regarding derivatives, see Note 11, Financial instruments and commodity contracts.Retained Interests. We retain certain interests in receivables sold in off-balance sheet securitization transactions. We estimate the fair value of retained interests using internal valuation models that incorporate market inputs and our own assumptions about future cash flows. The fair value of retained interests is estimated based on the present value of monthly collections on the sold finance receivables in excess of amounts accruing to investors and other obligations arising in securitization transactions. In addition to the amount of debt and collateral held by the securitization vehicle, the three key inputs that affect the valuation of the retained interests include credit losses, payment speed, and the discount rate. We classify these assets within Level 3. For more information regarding retained interests, see Note 3, Finance receivables.The following tables present the financial instruments measured at fair value on a recurring basis:   As of April  30, 2011  Level 1 Level 2 Level 3 Total(in millions)        Assets        Marketable securities:        U.S. treasury bills $383 $— $— $383Other U.S. and non-U.S. government bonds 335 — — 335Other 20 — — 20Derivative financial instruments:    Commodity contracts — 8 7 15Foreign currency contracts — 7 — 7Total assets $738 $15 $7 $760Liabilities        Derivative financial instruments:        Commodity contracts — — 1 1Total liabilities $— $— $1 $1   As of October 31, 2010  Level 1 Level 2 Level 3 Total(in millions)        Assets        Marketable securities:        U.S. treasury bills $159 $— $— $159Other U.S. and non-U.S. government bonds 407 — — 407Other 20 — — 20Derivative financial instruments:        Commodity contracts — — 2 2Foreign currency contracts — 8 — 8Retained interests — — 53 53Total assets $586 $8 $55 $649Liabilities        Derivative financial instruments:        Commodity contracts $— $4 $— $4Total liabilities $— $4 $— $4The table below presents the changes for those financial instruments classified within Level 3 of the valuation hierarchy: 2011  2010 Retainedinterests Commoditycontracts Interestrate swapassets andliabilities Retainedinterests Commoditycontracts(in millions)         Three Months Ended April 30         Balance at beginning of period$— $5 $— $315 $—Total gains (realized/unrealized) included in earnings(A)— 2 — 5 —Purchases, issuances and settlements— (1) — (97) —Balance at end of period$— $6 $— $223 $—Changes in unrealized gains on assets and liabilities still held$— $— $— $5 $—          Six Months Ended April 30         Balance at beginning of period$53 $2 $1 $291 $—Total gains (losses) (realized/unrealized) included in earnings(A)1 6 (1) — —Purchases, issuances and settlements(54) (2) — (68) —Balance at end of period$— $6 $— $223 $—Changes in unrealized gains on assets and liabilities still held$— $3 $— $— $—_____________ (A)For interest rate swap assets and liabilities, gains (losses) are included in Interest expense. For commodity contracts, gains (losses) are included in Cost of products sold. For retained interests, gains recognized are included in Finance revenues.The following table presents the financial instruments measured at fair value on a nonrecurring basis:   Level 2  April 30,2011 October 31,2010(in millions)    Finance receivables(A) $18 $27 _____________(A)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. As of April 30, 2011, impaired receivables with a carrying amount of $33 million had specific loss reserves of $15 million and a fair value of $18 million. As of October 31, 2010, impaired receivables with a carrying amount of $50 million had specific loss reserves of $23 million and a fair value of $27 million. Fair values of the underlying collateral are determined by reference to dealer vehicle value publications adjusted for certain market factors.In addition to the methods and assumptions we use for the financial instruments recorded at fair value as discussed above, we use the following methods and assumptions to estimate the fair value for our other financial instruments that are not marked to market on a recurring basis. The carrying amounts of cash and cash equivalents, restricted cash and cash equivalents, and accounts payable approximate fair values because of the short-term maturity and highly liquid nature of these instruments. The carrying amounts of customer receivables and retail and wholesale accounts approximate fair values as a result of the short-term nature of the receivables. Due to the nature of the aforementioned financial instruments, they have been excluded from the fair value amounts presented in the table below. The fair values of our finance receivables are estimated by discounting expected cash flows at estimated current market rates. We also use quoted market prices, when available, or the present value of estimated future cash flows to determine fair values of debt instruments.The carrying values and estimated fair values of financial instruments are summarized in the table below:   April 30, 2011 October 31, 2010  CarryingValue EstimatedFair  Value CarryingValue EstimatedFair  Value(in millions)        Assets        Finance receivables $2,365 $2,231 $2,465 $2,349Notes receivable 48 48 40 40Liabilities        Debt:        Manufacturing operations        8.25% Senior Notes, due 2021 966 1,156 965 1,1413.0% Senior Subordinated Convertible Notes, due 2014(A) 486 869 476 684Debt of majority-owned dealerships 93 89 66 63Financing arrangements 160 160 203 197Loan Agreement related to 6.5% Tax Exempt Bonds, due 2040 225 225 225 234Other 33 29 33 29Financial services operations        Asset-backed debt issued by consolidated SPEs, at various rates, due serially through 2018 1,769 1,803 1,731 1,773Bank revolvers, at fixed and variable rates, due dates from 2012 through 2018 942 949 974 984Commercial paper, at variable rates, due serially through 2012 55 55 67 67Borrowings secured by operating and finance leases, at various rates, due serially through 2017 88 89 112 113___________________ (A)The carrying value represents the financial statement amount of the debt after allocation of the conversion feature to equity, while the fair value is based on quoted market prices for the convertible note which includes the equity feature |

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| - Definition
Fair Value Measurements [Abstract]
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| - Definition
This item represents the complete disclosure regarding the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments, assets, and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the Company is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risk is are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 15B -Subparagraph a, bReference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 3, 10, 14, 15Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 44A, 44BReference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32, 33, 34Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 15C, 15DReference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 15A -Subparagraph a-dReference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 159 -Paragraph 17-22, 27, 28
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