Derivatives and Currency Exchange Risk Management , Net Investment Hedges and Fair Value Hedges (Details) - USD ($)	12 Months Ended
Apr. 26, 2019	Apr. 27, 2018	Apr. 28, 2017
Derivative [Line Items]
After-tax net unrealized gains (losses)	$ (169,000,000)	$ (257,000,000)
Net investment hedge unrealized gains or losses to be reclassified over the next twelve months, net of tax	0
Gains (losses) hedge ineffectiveness on net investment hedges	0	0	$ 0
Gains (losses) on firm commitments that no longer qualify as net investment hedges	0	0	0
Face value of debt	25,000,000,000.0	24,500,000,000
Gains (losses) hedge ineffectiveness on fair value hedges	0	0	0
Gains (losses) on firm commitments that no longer qualify as fair value hedges	0	0	$ 0
Senior Notes \| 4.125 percent ten-year 2011 senior notes
Derivative [Line Items]
Face value of debt	$ 500,000,000	$ 500,000,000
Stated interest rate	4.125%	4.125%
Senior Notes \| 3.125 percent ten-year 2012 senior notes
Derivative [Line Items]
Face value of debt	$ 675,000,000	$ 675,000,000
Stated interest rate	3.125%	3.125%
Currency exchange rate contracts
Derivative [Line Items]
Gross notional amount	$ 11,100,000,000	$ 11,500,000,000
Net investment hedges \| Derivatives designated as hedging instruments \| Currency exchange rate contracts
Derivative [Line Items]
Gross notional amount	7,800,000,000
Fair value hedges \| Derivatives designated as hedging instruments \| Interest rate swaps
Derivative [Line Items]
Gross notional amount	1,200,000,000	1,200,000,000
Unrealized gain (loss) on interest rate fair value hedging instruments	$ 9,000,000	$ (6,000,000)

Gain (Loss) from Hedged Firm Commitment Not Qualifying as Net Investment Hedge, Net

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- Definition

Net Investment Hedge Gain (Loss) to be Reclassified Within Twelve Months

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Unrealized Gain (Loss) on Net Investment Hedges, Accumulated Other Comprehensive Income (Loss), Net of Tax

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- Definition

Gain (loss) on hedging derivative instrument or the foreign currency transaction gain (loss) on the nonderivative hedging instrument designated as a hedge of a net investment in foreign operations related to hedge ineffectiveness, which is included in earnings in the period.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Nominal or face amount used to calculate payment on derivative.

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Amount of net gain (loss) recognized in earnings when a hedged firm commitment no longer qualifies as a fair value hedge.

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The net gain (loss) recognized in earnings during the period due to the ineffectiveness on interest rate fair value hedges.

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Amount of unrealized gain (loss) related to the fair value of interest rate derivatives designated as fair value hedging instruments, as offset by the gain (loss) on the hedged item to the extent that the fair value hedge is determined to be effective.

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