|**Allowance for Doubtful Accounts (Tables)**                            | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
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|**Allowance for Doubtful Accounts [Abstract]**                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Allowance For Credit Losses On Receivables [Table Text Block]           | The following tables present the activity related to our allowance for doubtful accounts for our retail portfolio segment, wholesale portfolio segment, and trade and other receivables:For the Year Ended October 31, 2019(in millions)RetailPortfolioWholesalePortfolioTrade andOtherReceivablesTotalAllowance for doubtful accounts, at beginning of period$19$3$28$50Provision for doubtful accounts5—(1)4Charge-off of accounts(6)—(6)(12)Recoveries2——2Other(A)————Allowance for doubtful accounts, at end of period$20$3$21$44For the Year Ended October 31, 2018(in millions)RetailPortfolioWholesalePortfolioTrade andOtherReceivablesTotalAllowance for doubtful accounts, at beginning of period$17$3$28$48Provision for doubtful accounts7—310Charge-off of accounts(7)—(1)(8)Recoveries3——3Other(A)(1)—(2)(3)Allowance for doubtful accounts, at end of period$19$3$28$50For the Year Ended October 31, 2017(in millions)Retail PortfolioWholesale PortfolioTrade and Other ReceivablesTotalAllowance for doubtful accounts, at beginning of period$19$2$28$49Provision for doubtful accounts4127Charge-off of accounts(7)—(1)(8)Recoveries1——1Other(A)——(1)(1)Allowance for doubtful accounts, at end of period$17$3$28$48____________________(A)Amounts include impact from currency translation.
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|                                                                        | For the Year Ended October 31, 2019                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
|(in millions)                                                           | RetailPortfolio                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Allowance for doubtful accounts, at beginning of period                 | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Provision for doubtful accounts                                         | 5                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Charge-off of accounts                                                  | (6                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
|Recoveries                                                              | 2                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Other(A)                                                                | —                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Allowance for doubtful accounts, at end of period                       | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
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|                                                                        | For the Year Ended October 31, 2018                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
|(in millions)                                                           | RetailPortfolio                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Allowance for doubtful accounts, at beginning of period                 | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Provision for doubtful accounts                                         | 7                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Charge-off of accounts                                                  | (7                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
|Recoveries                                                              | 3                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Other(A)                                                                | (1                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
|Allowance for doubtful accounts, at end of period                       | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
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|                                                                        | For the Year Ended October 31, 2017                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
|(in millions)                                                           | Retail Portfolio                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
|Allowance for doubtful accounts, at beginning of period                 | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Provision for doubtful accounts                                         | 4                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Charge-off of accounts                                                  | (7                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
|Recoveries                                                              | 1                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Other(A)                                                                | —                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Allowance for doubtful accounts, at end of period                       | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Impaired Financing Receivables [Table Text Block]                       | The following table presents information regarding impaired finance receivables:October 31, 2019October 31, 2018(in millions)RetailPortfolioWholesalePortfolioTotalRetailPortfolioWholesalePortfolioTotalImpaired finance receivables with specific loss reserves$23$—$23$20$—$20Impaired finance receivables without specific loss reserves1—1———Specific loss reserves on impaired finance receivables11—119—9Finance receivables on non-accrual status24—2420—20                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             
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|                                                                        | October 31, 2019                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
|(in millions)                                                           | RetailPortfolio                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Impaired finance receivables with specific loss reserves                | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Impaired finance receivables without specific loss reserves             | 1                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Specific loss reserves on impaired finance receivables                  | 11                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
|Finance receivables on non-accrual status                               | 24                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
|Allowance for Credit Losses on Financing Receivables [Table Text Block] | use the aging of our receivables as well as other inputs when assessing credit quality. The following table presents the aging analysis for finance receivables:October 31, 2019October 31, 2018(in millions)RetailPortfolioWholesalePortfolioTotalRetailPortfolioWholesalePortfolioTotalCurrent, and less than 30 days past due$753$1,365$2,118$655$1,459$2,11430-90 days past due7617751152Over 90 days past due25—2514—14Total finance receivables$854$1,366$2,220$720$1,460$2,180                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           
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|                                                                        | October 31, 2019                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
|(in millions)                                                           | RetailPortfolio                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 
|Current, and less than 30 days past due                                 | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|30-90 days past due                                                     | 76                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
|Over 90 days past due                                                   | 25                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              
|Total finance receivables                                               | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               

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