Balance Sheet Details - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
Jan. 31, 2019	Oct. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Contract liabilities	$ 5,800	$ 3,200
Deferred revenue for financing activities	91	$ 82
Unearned revenue recognized	1,700
Unsatisfied performance obligations	5,800
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Current portion of capitalized costs	41
Non-current portion of capitalized costs	63
Amortization of capitalized costs to obtain a contract	$ 10
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-02-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Unsatisfied performance obligation expected to be recognized over the remainder of the year	46.00%

Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

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Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer; classified as current.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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The noncurrent portion of deferred revenue amount as of balance sheet date. Deferred revenue is a liability related to a revenue producing activity for which revenue has not yet been recognized, and is not expected to be recognized in the next twelve months. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

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