Derivatives and Currency Exchange Risk Management , Freestanding Derivative Forward Contracts and Cash Flow Hedges (Details) - USD ($)	12 Months Ended
Apr. 28, 2017	Apr. 29, 2016	Apr. 24, 2015
Derivative Instruments
Gains (losses) relating to ineffectiveness of cash flow hedges	$ 0	$ 0	$ 0
Gains (losses) relating to ineffectiveness of forward starting interest rate derivative instruments	0	0	0
After-tax net unrealized gains (losses)	37,000,000	(90,000,000)
Cash flow hedge unrealized gains to be reclassified over the next twelve months, net of tax	73,000,000
Currency exchange rate contracts
Derivative Instruments
Gross notional amount	10,800,000,000	10,800,000,000
Interest rate swaps
Derivative Instruments
Recognized in AOCI	$ 363,000,000	(164,000,000)
Weighted average fixed rate of interest rate derivatives	3.10%
Market value of derivative instruments - unrealized (loss) gain	$ 0	(48,000,000)
Other expense, net \| Currency exchange rate contracts
Derivative Instruments
Currency exchange rate contracts	54,000,000	33,000,000	210,000,000
Cash flow hedges
Derivative Instruments
Recognized in AOCI	342,000,000	(165,000,000)	707,000,000
Recognized in Income	173,000,000	368,000,000	156,000,000
Cash flow hedges \| Currency exchange rate contracts
Derivative Instruments
Recognized in AOCI	342,000,000	(165,000,000)	707,000,000
Cash flow hedges \| Other expense, net \| Currency exchange rate contracts
Derivative Instruments
Recognized in Income	173,000,000	405,000,000	221,000,000
Cash flow hedges \| Cost of products sold \| Currency exchange rate contracts
Derivative Instruments
Recognized in Income		(37,000,000)	$ (65,000,000)
Derivatives not designated as hedging instruments \| Currency exchange rate contracts
Derivative Instruments
Gross notional amount	4,900,000,000	5,000,000,000
Derivatives designated as hedging instruments \| Cash flow hedges \| Currency exchange rate contracts
Derivative Instruments
Gross notional amount	$ 5,800,000,000	$ 5,700,000,000
Derivative term	3 years	3 years
Derivatives designated as hedging instruments \| Cash flow hedges \| Interest rate swaps
Derivative Instruments
Gross notional amount		$ 300,000,000
Payments for hedge upon termination	$ 27,000,000	45,000,000
Derivative, notional amount terminated		$ 500,000,000

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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Notional amount of derivative(s) terminated. Expressed as an absolute value.

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No definition available.

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Amount of unrealized gain (loss), net of tax as of the balance sheet date, related to the increase or decrease in fair value of interest rate derivatives designated as cash flow hedging instruments, which was recorded in accumulated other comprehensive income to the extent that the cash flow hedge was determined to be effective.

+ References

No definition available.

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The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80748-113994

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Average fixed interest rate related to the group of interest rate derivatives.

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624177-113959

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The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The net gain (loss) during the reporting period due to ineffectiveness in foreign currency cash flow hedges. Recognized in earnings.

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Amount of gain (loss) recognized in earnings in the period from the increase (decrease) in fair value of foreign currency derivatives not designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959

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The net gain (loss) during the reporting period due to ineffectiveness in interest rate cash flow hedges. Recognized in earnings.

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The cash outflow for a financial contract that meets the hedge criteria as either cash flow hedge, fair value hedge or hedge of net investment in foreign operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 27
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3581-108585

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Amount of unrealized gain (loss) related to derivatives designated as cash flow hedging instruments, recorded in results of operations to the extent that the cash flow hedge is determined to be ineffective.

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