Consolidated Comprehensive Income (Parenthetical) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jan. 25, 2014	Jan. 26, 2013	Jan. 25, 2014	Jan. 26, 2013
Other Comprehensive Income (Loss), Tax
Available-for-sale Securities, before Reclassification Adjustments, Tax	$ (69)	$ (47)	$ (122)	$ (46)
Reclassification Adjustment for Sale of Securities Included in Net Income, Tax	31	5	62	14
Derivatives Qualifying as Hedges, Tax	1	(1)	(2)	(1)
Foreign Currency Translation Adjustment, Tax	$ 2	$ (5)	$ (1)	$ (15)

Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities and unrealized holding gain (loss) related to transfers of securities into the available-for-sale category and out of the held-to-maturity category.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 12

-URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e640-108580

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Amount of tax expense (benefit), after reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=28358780&loc=SL7669646-108580

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Amount of tax expense (benefit), after reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 10A

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=28358780&loc=SL7669646-108580

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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