Financial Instruments and Fair Value Measurements - Summary of Investments (Detail) - USD ($) $ in Millions	Jan. 24, 2020	Apr. 26, 2019
Schedule of Available-for-sale Securities [Line Items]
Cost or amortized cost	$ 499	$ 1,725
Gross unrealized gains	1	2
Gross unrealized losses	0	(9)
Estimated fair value	500	1,718
Corporate Bonds
Schedule of Available-for-sale Securities [Line Items]
Cost or amortized cost	219	1,359
Gross unrealized gains	1	2
Gross unrealized losses	0	(8)
Estimated fair value	220	1,353
U.S. Treasury and Government Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Cost or amortized cost	83	214
Gross unrealized gains	0	0
Gross unrealized losses	0	(1)
Estimated fair value	83	213
Certificates of Deposit
Schedule of Available-for-sale Securities [Line Items]
Cost or amortized cost	159	117
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Estimated fair value	159	117
Mutual Funds
Schedule of Available-for-sale Securities [Line Items]
Cost or amortized cost	38	35
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Estimated fair value	$ 38	$ 35

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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