Cash, Cash Equivalents and Investments - Gain (Loss) on Equity Investments (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Apr. 26, 2020	Apr. 28, 2019	Apr. 26, 2020	Apr. 28, 2019
Gain (Loss) on Securities [Line Items]
Total gain (loss) on equity investments, net	$ (7)	$ 11	$ (11)	$ 23
Publicly traded equity securities
Gain (Loss) on Securities [Line Items]
Unrealized gain	3	7	5	13
Unrealized loss	(12)	(1)	(15)	(3)
Realized gain on sales	0	1	0	2
Equity investments in privately-held companies
Gain (Loss) on Securities [Line Items]
Unrealized gain	9	2	9	9
Unrealized loss	(2)	(2)	(3)	(3)
Realized gain on sales	1	4	1	5
Realized loss on sales or impairment	$ (6)	$ 0	$ (8)	$ 0

Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=116654751&loc=SL75117546-209714

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Amount of realized gain from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=116654751&loc=SL75117546-209714

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Amount of realized loss from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of unrealized gain on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of unrealized loss on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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