Financial Instruments and Fair Value Measurements - Summary of Investments (Detail) - USD ($) $ in Millions	Oct. 28, 2016	Apr. 29, 2016
Schedule of Available-for-sale Securities [Line Items]
Cost or amortized cost	$ 2,510	$ 2,613
Gross unrealized gains	5	7
Gross unrealized losses	(2)	(1)
Estimated fair value	2,513	2,619
Corporate Bonds
Schedule of Available-for-sale Securities [Line Items]
Cost or amortized cost	1,234	1,370
Gross unrealized gains	4	5
Gross unrealized losses	(1)	(1)
Estimated fair value	1,237	1,374
U.S. Treasury and Government Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Cost or amortized cost	669	878
Gross unrealized gains	1	2
Gross unrealized losses	(1)	0
Estimated fair value	669	880
Foreign Government Debt Securities
Schedule of Available-for-sale Securities [Line Items]
Cost or amortized cost	27	35
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Estimated fair value	27	35
Commercial Paper
Schedule of Available-for-sale Securities [Line Items]
Cost or amortized cost	476	202
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Estimated fair value	476	202
Certificates of Deposit
Schedule of Available-for-sale Securities [Line Items]
Cost or amortized cost	72	98
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Estimated fair value	72	98
Mutual Funds
Schedule of Available-for-sale Securities [Line Items]
Cost or amortized cost	32	30
Gross unrealized gains	0	0
Gross unrealized losses	0	0
Estimated fair value	$ 32	$ 30