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The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices of vested portions of options outstanding and currently exercisable under the option plan as of the balance sheet date.

+ References

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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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(c), d(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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-Name Accounting Standards Codification

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-SubTopic 10

-Section 50

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-Subparagraph (c)(1)(iii)

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(c)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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- Definition

The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices pertaining to options outstanding under the plan as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph d(1)

-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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-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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- Definition

The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(a)

-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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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(b)

-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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- Definition

The weighted average price as of the beginning of the year at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(a)

-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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-Publisher FASB

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- Definition

The weighted average period between the balance sheet date and expiration for all awards outstanding under the plan, which may be expressed in a decimal value for number of years.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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-Paragraph 2

-Subparagraph (e)(1)

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Employee Stock Plans (Summary Of Significant Ranges Of Outstanding And Exercisable Stock Options) (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	Oct. 27, 2012 Y	Jul. 30, 2012	Jul. 28, 2012	Oct. 29, 2011	Jul. 30, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding	442		520		621
Stock options outstanding, weighted-average remaining contractual life (in years)	2.55
Stock options outstanding, weighted-average exercise price per share	$ 23.15		$ 22.68		$ 21.79
Stock options outstanding, aggregate intrinsic value	$ 80
Stock options exercisable	438	512
Stock options exercisable, weighted-average exercise price per share	$ 23.17			$ 22.65
Stock options exercisable, aggregate intrinsic value	72
Price 0.01 To 15.00 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding	8
Stock options outstanding, weighted-average remaining contractual life (in years)	3.80
Stock options outstanding, weighted-average exercise price per share	$ 7.57
Stock options outstanding, aggregate intrinsic value	78
Stock options exercisable	7
Stock options exercisable, weighted-average exercise price per share	$ 7.88
Stock options exercisable, aggregate intrinsic value	70
Price 15.01 To 18.00 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding	76
Stock options outstanding, weighted-average remaining contractual life (in years)	1.90
Stock options outstanding, weighted-average exercise price per share	$ 17.79
Stock options outstanding, aggregate intrinsic value	2
Stock options exercisable	76
Stock options exercisable, weighted-average exercise price per share	$ 17.79
Stock options exercisable, aggregate intrinsic value	2
Price 18.01 To 20.00 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding	95
Stock options outstanding, weighted-average remaining contractual life (in years)	1.10
Stock options outstanding, weighted-average exercise price per share	$ 19.17
Stock options outstanding, aggregate intrinsic value	0
Stock options exercisable	95
Stock options exercisable, weighted-average exercise price per share	$ 19.17
Stock options exercisable, aggregate intrinsic value	0
Price 20.01 To 25.00 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding	135
Stock options outstanding, weighted-average remaining contractual life (in years)	2.66
Stock options outstanding, weighted-average exercise price per share	$ 22.78
Stock options outstanding, aggregate intrinsic value	0
Stock options exercisable	134
Stock options exercisable, weighted-average exercise price per share	$ 22.78
Stock options exercisable, aggregate intrinsic value	0
Price 25.01 To 35.00 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding	128
Stock options outstanding, weighted-average remaining contractual life (in years)	3.84
Stock options outstanding, weighted-average exercise price per share	$ 30.66
Stock options outstanding, aggregate intrinsic value	0
Stock options exercisable	126
Stock options exercisable, weighted-average exercise price per share	$ 30.70
Stock options exercisable, aggregate intrinsic value	$ 0