Taxes on Earnings Schedule of Activity Related to Unrecognized Tax Benefits (Details) - USD ($) $ in Millions	12 Months Ended
Jul. 31, 2016	Aug. 02, 2015	Aug. 03, 2014
Income Tax Disclosure [Abstract]
Unrecognized Tax Benefits	$ 58	$ 71	$ 61
Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions	2	9	0
Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions	0	0	(1)
Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions	3	5	11
Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities	0	(27)	0
Unrecognized Tax Benefits, Reduction Resulting from Lapse of Applicable Statute of Limitations	0	0	0
Unrecognized Tax Benefits	$ 63	$ 58	$ 71

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- Definition

Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Unrecognized Tax Benefit
-URI http://asc.fasb.org/extlink&oid=6527854

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from settlements with taxing authorities.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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