Supplementary Financial Information - Other Current Assets (Details) - USD ($) $ in Millions	Jan. 31, 2020	Oct. 31, 2019
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Supplier and other receivables	$ 1,272	$ 1,951
Prepaid and other current assets	1,022	967
Value-added taxes receivable	887	957
Available-for-sale investments	288	0
Other current assets	$ 3,469	$ 3,875

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as current.

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The sum of amounts currently receivable other than from customers. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

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Amount of current assets classified as other.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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Carrying amount as of the balance sheet date of value added taxes due either from customers arising from sales on credit terms, or as previously overpaid to tax authorities. For classified balance sheets, represents the current amount receivable, that is amounts expected to be collected within one year or the normal operating cycle, if longer.

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