Financial Instruments - Activity Related to the Company's Investment Portfolio, Equity and Other Investments (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jan. 24, 2020	Jan. 25, 2019	Jan. 24, 2020	Jan. 25, 2019
Investment [Line Items]
Proceeds from sales			$ 5,791	$ 4,159
Equity and Other Investments
Investment [Line Items]
Proceeds from sales	$ 0	$ 33	2	941
Gross gains	1	8	16	131
Gross losses	0	(1)	0	(30)
Impairment losses recognized	$ (1)	$ 0	$ (5)	$ (12)

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI http://asc.fasb.org/extlink&oid=118954083&loc=SL6284422-111562

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration