Supplemental Cash Flow Information (Schedule Of Statements Of Cash Flows) (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
Jan. 27, 2013	Jan. 29, 2012
Supplemental Cash Flow Information [Abstract]
Benefit related payments	$ (17)	$ (20)
Other	0	(4)
Total other cash used in operating activities	$ (17)	$ (24)

The sum of adjustments which are added to or deducted from net income or loss, including the portion attributable to noncontrolling interest, to reflect cash provided by or used in operating activities, in accordance with the indirect cash flow method.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 95

-Paragraph 28

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration