Allowance for Credit Losses - Schedule of Impaired Finance Receivables (Details) - USD ($) $ in Millions	Apr. 30, 2021	Oct. 31, 2020
Impaired finance receivables with specific loss reserves
Finance Receivable, Impaired [Line Items]
Impaired financing receivables	$ 46	$ 31
Impaired finance receivables with specific loss reserves \| Retail portfolio
Finance Receivable, Impaired [Line Items]
Impaired financing receivables	46	31
Impaired finance receivables with specific loss reserves \| Wholesale portfolio
Finance Receivable, Impaired [Line Items]
Impaired financing receivables	0	0
Impaired finance receivables without specific loss reserves
Finance Receivable, Impaired [Line Items]
Impaired financing receivables	0	0
Impaired finance receivables without specific loss reserves \| Retail portfolio
Finance Receivable, Impaired [Line Items]
Impaired financing receivables	0	0
Impaired finance receivables without specific loss reserves \| Wholesale portfolio
Finance Receivable, Impaired [Line Items]
Impaired financing receivables	0	0
Specific loss reserves on impaired finance receivables
Finance Receivable, Impaired [Line Items]
Specific loss reserves on impaired finance receivables	14	12
Specific loss reserves on impaired finance receivables \| Retail portfolio
Finance Receivable, Impaired [Line Items]
Specific loss reserves on impaired finance receivables	14	12
Specific loss reserves on impaired finance receivables \| Wholesale portfolio
Finance Receivable, Impaired [Line Items]
Specific loss reserves on impaired finance receivables	0	0
Finance receivables on non-accrual status
Finance Receivable, Impaired [Line Items]
Finance receivables on non-accrual status	29	31
Finance receivables on non-accrual status \| Retail portfolio
Finance Receivable, Impaired [Line Items]
Finance receivables on non-accrual status	29	31
Finance receivables on non-accrual status \| Wholesale portfolio
Finance Receivable, Impaired [Line Items]
Finance receivables on non-accrual status	$ 0	$ 0

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No definition available.

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- Definition

Amount of financing receivable on nonaccrual status.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5111-111524

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919258-210447

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- Definition

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953550-111524

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- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

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