Derivatives and Currency Exchange Risk Management , Offsetting of Assets and Liabilities (Details) - USD ($) $ in Millions	Apr. 26, 2019	Apr. 27, 2018
Derivative assets:
Gross Amount of Recognized Assets (Liabilities)	$ 365	$ 118
Gross Amount Not Offset on the Balance Sheet, Financial Instruments	(9)	(71)
Gross Amount Not Offset on the Balance Sheet, Cash Collateral (Received) Posted	(44)	0
Gross Amount Not Offset on the Balance Sheet, Securities Collateral (Received) Posted	0	0
Net Amount	312	47
Derivative liabilities:
Gross Amount of Recognized Assets (Liabilities)	(19)	(258)
Gross Amount Not Offset on the Balance Sheet, Financial Instruments	9	71
Gross Amount Not Offset on the Balance Sheet, Cash Collateral (Received) Posted	0	0
Gross Amount Not Offset on the Balance Sheet, Securities Collateral (Received) Posted	0	76
Net Amount	(10)	(111)
Total
Gross Amount of Recognized Assets (Liabilities)	346	(140)
Gross Amount Not Offset on the Balance Sheet, Financial Instruments	0	0
Gross Amount Not Offset on the Balance Sheet, Cash Collateral (Received) Posted	(44)	0
Gross Amount Not Offset on the Balance Sheet, Securities Collateral (Received) Posted	0	76
Net Amount	302	(64)
Currency exchange rate contracts
Derivative assets:
Gross Amount of Recognized Assets (Liabilities)	335	79
Gross Amount Not Offset on the Balance Sheet, Financial Instruments	(9)	(61)
Gross Amount Not Offset on the Balance Sheet, Cash Collateral (Received) Posted	(43)	0
Gross Amount Not Offset on the Balance Sheet, Securities Collateral (Received) Posted	0	0
Net Amount	283	18
Derivative liabilities:
Gross Amount of Recognized Assets (Liabilities)	(19)	(238)
Gross Amount Not Offset on the Balance Sheet, Financial Instruments	9	61
Gross Amount Not Offset on the Balance Sheet, Cash Collateral (Received) Posted	0	0
Gross Amount Not Offset on the Balance Sheet, Securities Collateral (Received) Posted	0	74
Net Amount	(10)	(103)
Interest rate contracts
Derivative assets:
Gross Amount of Recognized Assets (Liabilities)	9	8
Gross Amount Not Offset on the Balance Sheet, Financial Instruments	0	(6)
Gross Amount Not Offset on the Balance Sheet, Cash Collateral (Received) Posted	(1)	0
Gross Amount Not Offset on the Balance Sheet, Securities Collateral (Received) Posted	0	0
Net Amount	8	2
Derivative liabilities:
Gross Amount of Recognized Assets (Liabilities)		(14)
Gross Amount Not Offset on the Balance Sheet, Financial Instruments		6
Gross Amount Not Offset on the Balance Sheet, Cash Collateral (Received) Posted		0
Gross Amount Not Offset on the Balance Sheet, Securities Collateral (Received) Posted		2
Net Amount		(6)
Total return swaps
Derivative assets:
Gross Amount of Recognized Assets (Liabilities)	15	4
Gross Amount Not Offset on the Balance Sheet, Financial Instruments	0	0
Gross Amount Not Offset on the Balance Sheet, Cash Collateral (Received) Posted	0	0
Gross Amount Not Offset on the Balance Sheet, Securities Collateral (Received) Posted	0	0
Net Amount	15	4
Stock warrants
Derivative assets:
Gross Amount of Recognized Assets (Liabilities)		21
Gross Amount Not Offset on the Balance Sheet, Financial Instruments		0
Gross Amount Not Offset on the Balance Sheet, Cash Collateral (Received) Posted		0
Gross Amount Not Offset on the Balance Sheet, Securities Collateral (Received) Posted		0
Net Amount		21
Cross-currency interest rate contracts
Derivative assets:
Gross Amount of Recognized Assets (Liabilities)	6	6
Gross Amount Not Offset on the Balance Sheet, Financial Instruments	0	(4)
Gross Amount Not Offset on the Balance Sheet, Cash Collateral (Received) Posted	0	0
Gross Amount Not Offset on the Balance Sheet, Securities Collateral (Received) Posted	0	0
Net Amount	$ 6	2
Derivative liabilities:
Gross Amount of Recognized Assets (Liabilities)		(6)
Gross Amount Not Offset on the Balance Sheet, Financial Instruments		4
Gross Amount Not Offset on the Balance Sheet, Cash Collateral (Received) Posted		0
Gross Amount Not Offset on the Balance Sheet, Securities Collateral (Received) Posted		0
Net Amount		$ (2)

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Derivative, Assets And Liabilities, Net, Collateral, Right to Reclaim Securities

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Fair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be offset, deducted from derivative assets.

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Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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