Financial Instruments and Fair Value Measurements - Summary of Investments (Detail) - USD ($) $ in Millions	Apr. 29, 2016	Apr. 24, 2015
Schedule of Available-for-sale Securities [Line Items]
Cost or amortized cost	$ 2,613	$ 3,681
Gross unrealized gains	7	11
Gross unrealized losses	(1)	0
Estimated fair value	2,619	3,692
Corporate Bonds
Schedule of Available-for-sale Securities [Line Items]
Cost or amortized cost	1,370	2,249
Gross unrealized gains	5	9
Gross unrealized losses	(1)	0
Estimated fair value	1,374	2,258
U.S. Treasury and Government Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Cost or amortized cost	878	1,056
Gross unrealized gains	2	2
Gross unrealized losses	0	0
Estimated fair value	880	1,058
Foreign Government Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Cost or amortized cost	35	38
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Estimated fair value	35	38
Commercial Paper
Schedule of Available-for-sale Securities [Line Items]
Cost or amortized cost	202	20
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Estimated fair value	202	20
Certificates of Deposit
Schedule of Available-for-sale Securities [Line Items]
Cost or amortized cost	98	286
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Estimated fair value	98	286
Mutual Funds
Schedule of Available-for-sale Securities [Line Items]
Cost or amortized cost	30	32
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Estimated fair value	$ 30	$ 32

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
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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.

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