Derivatives and Foreign Exchange Risk Management - Gains (Losses) on Derivatives and Amounts Reclassified into Income (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Oct. 30, 2015	Oct. 24, 2014	Oct. 30, 2015	Oct. 24, 2014
Other expense, net [Member] \| Foreign currency exchange rate contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Foreign currency exchange rate contracts gains (losses)	$ (4)	$ 73	$ 16	$ 49
Cash flow hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gross Gains (Losses) Recognized in OCI on Effective Portion of Derivative	17	229	3	291
Effective Portion of Gains (Losses) on Derivative Reclassified from AOCI into Income	74	21	148	19
Cash flow hedging [Member] \| Foreign currency exchange rate contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gross Gains (Losses) Recognized in OCI on Effective Portion of Derivative	17	229	3	291
Cash flow hedging [Member] \| Other expense, net [Member] \| Foreign currency exchange rate contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Effective Portion of Gains (Losses) on Derivative Reclassified from AOCI into Income	89	20	184	21
Cash flow hedging [Member] \| Cost of products sold [Member] \| Foreign currency exchange rate contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Effective Portion of Gains (Losses) on Derivative Reclassified from AOCI into Income	$ (15)	$ 1	$ (36)	$ (2)

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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=56946850&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=56946850&loc=SL5624177-113959

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- Definition

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.

+ References

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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=56946850&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 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5618551-113959

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