Supplementary Financial Information - Other Non-Current Assets (Details) - USD ($) $ in Millions	Jul. 31, 2020	Oct. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Deferred tax assets	$ 2,506	$ 2,620
Right-of-use assets from operating leases, net	1,099	0
Intangible assets	572	661
Other	754	843
Other non-current assets	4,931	4,124
Equity securities	$ 57	$ 56

Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 926
-SubTopic 20
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Amount of lessee's right to use underlying asset under operating lease.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
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Amount of other miscellaneous assets expected to be realized or consumed after one year or normal operating cycle, if longer.

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Amount of noncurrent assets classified as other.

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