Derivatives and Currency Exchange Risk Management - Offsetting Assets and Liabilities (Details) - USD ($) $ in Millions	Oct. 27, 2017	Apr. 28, 2017
Offsetting Assets and Liabilities [Line Items]
Derivative Assets, Gross Amount of Recorded Assets (Liabilities)	$ 206	$ 262
Derivative Assets, Gross Amount Not Offset on the Balance Sheet, Financial Instruments	(125)	(75)
Derivative Assets, Gross Amount Not Offset on the Balance Sheet, Collateral (Received) or Posted	0	(60)
Derivative Assets, Net Amount	81	127
Derivative Liabilities, Gross Amount of Recorded Assets (Liabilities)	(211)	(104)
Derivative Liabilities, Gross Amount Not Offset on the Balance Sheet, Financial Instruments	125	75
Derivative Liabilities, Gross Amount Not Offset on the Balance Sheet, Collateral (Received) or Posted	0	0
Derivative Liabilities, Net Amount	(86)	(29)
Gross Amount of Recorded Assets (Liabilities)	(5)	158
Gross Amount Not Offset on the Balance Sheet, Financial Instruments	0	0
Gross Amount Not Offset on the Balance Sheet, Collateral (Received) or Posted	0	(60)
Net Amount	(5)	98
Currency exchange rate contracts
Offsetting Assets and Liabilities [Line Items]
Derivative Assets, Gross Amount of Recorded Assets (Liabilities)	137	216
Derivative Assets, Gross Amount Not Offset on the Balance Sheet, Financial Instruments	(110)	(58)
Derivative Assets, Gross Amount Not Offset on the Balance Sheet, Collateral (Received) or Posted	0	(55)
Derivative Assets, Net Amount	27	103
Derivative Liabilities, Gross Amount of Recorded Assets (Liabilities)	(203)	(93)
Derivative Liabilities, Gross Amount Not Offset on the Balance Sheet, Financial Instruments	123	73
Derivative Liabilities, Gross Amount Not Offset on the Balance Sheet, Collateral (Received) or Posted	0	0
Derivative Liabilities, Net Amount	(80)	(20)
Interest rate contracts
Offsetting Assets and Liabilities [Line Items]
Derivative Assets, Gross Amount of Recorded Assets (Liabilities)	30	41
Derivative Assets, Gross Amount Not Offset on the Balance Sheet, Financial Instruments	(13)	(15)
Derivative Assets, Gross Amount Not Offset on the Balance Sheet, Collateral (Received) or Posted	0	(5)
Derivative Assets, Net Amount	17	21
Cross currency interest rate contracts
Offsetting Assets and Liabilities [Line Items]
Derivative Assets, Gross Amount of Recorded Assets (Liabilities)	6	5
Derivative Assets, Gross Amount Not Offset on the Balance Sheet, Financial Instruments	(2)	(2)
Derivative Assets, Gross Amount Not Offset on the Balance Sheet, Collateral (Received) or Posted	0	0
Derivative Assets, Net Amount	4	3
Derivative Liabilities, Gross Amount of Recorded Assets (Liabilities)	(8)	(11)
Derivative Liabilities, Gross Amount Not Offset on the Balance Sheet, Financial Instruments	2	2
Derivative Liabilities, Gross Amount Not Offset on the Balance Sheet, Collateral (Received) or Posted	0	0
Derivative Liabilities, Net Amount	(6)	$ (9)
Stock warrants
Offsetting Assets and Liabilities [Line Items]
Derivative Assets, Gross Amount of Recorded Assets (Liabilities)	25
Derivative Assets, Gross Amount Not Offset on the Balance Sheet, Financial Instruments	0
Derivative Assets, Gross Amount Not Offset on the Balance Sheet, Collateral (Received) or Posted	0
Derivative Assets, Net Amount	25
Total return swap
Offsetting Assets and Liabilities [Line Items]
Derivative Assets, Gross Amount of Recorded Assets (Liabilities)	8
Derivative Assets, Gross Amount Not Offset on the Balance Sheet, Financial Instruments	0
Derivative Assets, Gross Amount Not Offset on the Balance Sheet, Collateral (Received) or Posted	0
Derivative Assets, Net Amount	$ 8