Acquisitions (Details) - USD ($) $ in Millions	Nov. 01, 2018	Apr. 30, 2019	Oct. 31, 2018
Business Combinations [Abstract]
Goodwill	$ 375	$ 6,349	$ 5,968
Amortizable intangible assets	300
Net liabilities assumed	(186)
Total fair value of consideration	$ 489

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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- Definition

Amount of liabilities assumed at the acquisition date.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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