Employee Benefit Plans (Summary Of Share-Based Awards Available For Grant) (Detail) In Millions, unless otherwise specified	6 Months Ended	12 Months Ended
Jan. 26, 2013	Jul. 28, 2012
Share-based Compensation Arrangement by Share-based Payment Award, Options Available for Grant [Roll Forward]
Beginning balance	218	255
Restricted stock, stock units, and other share-based awards granted and assumed	(78)	(95)
Share-based awards canceled/forfeited/expired	89	64
Stock Option And Other Share Based Awards Granted	(3)	(6)
Ending balance	226	218

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant