Supplementary Financial Information - Other Non-Current Assets (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jul. 31, 2018	Jul. 31, 2018	Oct. 31, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Tax indemnifications receivable	$ 908	$ 908	$ 1,695
Deferred tax assets	1,992	1,992	342
Other	1,536	1,536	1,058
Other non-current assets	4,436	4,436	3,095
Adjustment to indemnification receivable	676	671
Available-for-sale Securities, Equity Securities, Noncurrent	$ 57	$ 57	$ 61

Change in Tax Indemnification

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- Definition

Amount of tax indemnified receivable non-current associated with the Tax Matters Agreement.

+ References

No definition available.

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- Definition

Equity securities categorized neither as held-to-maturity nor trading which are intended be sold more than one year from the balance sheet date or operating cycle, if longer.

+ References

No definition available.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards classified as noncurrent.

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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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