Income Taxes (Breakdown Between Current and Noncurrent Net Deferred Tax Assets) (Details) - USD ($) $ in Millions	Jul. 29, 2017	Jul. 30, 2016
Income Tax Disclosure [Abstract]
Deferred tax assets	$ 4,239	$ 4,299
Deferred tax liabilities	(271)	(278)
Total net deferred tax assets	$ 3,968	$ 4,021

Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, with jurisdictional netting.

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Amount, after deferred tax asset, of deferred tax liability attributable to taxable differences with jurisdictional netting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=84176650&loc=d3e31931-109318

+ Details

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

+ References

+ Details

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- References

No definition available.

+ Details

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