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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

+ References

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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 Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

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

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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

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

+ Details

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ 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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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

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

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- Definition

Weighted average price 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 Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)

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

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (e)(1)

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

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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)

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

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- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)

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

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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	6 Months Ended
	Jan. 25, 2014	Jul. 27, 2013	Jul. 28, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options outstanding (in shares)	238	276	520
Stock options outstanding, weighted-average remaining contractual life	2 years 0 months 11 days
Stock options outstanding, weighted-average exercise price per share	$ 24.70	$ 24.44	$ 22.68
Stock options outstanding, aggregate intrinsic value	$ 381
Stock options exercisable (in shares)	232	271
Stock options exercisable, weighted-average exercise price per share	$ 25.24	$ 24.84
Stock options exercisable, aggregate intrinsic value	268
$0.01 - 15.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise price of stock options outstanding and exercisable, minimum	$ 0.01
Range of exercise price of stock options outstanding and exercisable, maximum	$ 15.00
Stock options outstanding (in shares)	11
Stock options outstanding, weighted-average remaining contractual life	5 years 5 months 1 day
Stock options outstanding, weighted-average exercise price per share	$ 4.35
Stock options outstanding, aggregate intrinsic value	201
Stock options exercisable (in shares)	5
Stock options exercisable, weighted-average exercise price per share	$ 6.33
Stock options exercisable, aggregate intrinsic value	88
$15.01 - 18.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise price of stock options outstanding and exercisable, minimum	$ 15.01
Range of exercise price of stock options outstanding and exercisable, maximum	$ 18.00
Stock options outstanding (in shares)	32
Stock options outstanding, weighted-average remaining contractual life	8 months 16 days
Stock options outstanding, weighted-average exercise price per share	$ 17.80
Stock options outstanding, aggregate intrinsic value	140
Stock options exercisable (in shares)	32
Stock options exercisable, weighted-average exercise price per share	$ 17.80
Stock options exercisable, aggregate intrinsic value	140
$18.01 - 20.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise price of stock options outstanding and exercisable, minimum	$ 18.01
Range of exercise price of stock options outstanding and exercisable, maximum	$ 20.00
Stock options outstanding (in shares)	10
Stock options outstanding, weighted-average remaining contractual life	8 months 8 days
Stock options outstanding, weighted-average exercise price per share	$ 19.13
Stock options outstanding, aggregate intrinsic value	30
Stock options exercisable (in shares)	10
Stock options exercisable, weighted-average exercise price per share	$ 19.13
Stock options exercisable, aggregate intrinsic value	30
$20.01 - 25.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise price of stock options outstanding and exercisable, minimum	$ 20.01
Range of exercise price of stock options outstanding and exercisable, maximum	$ 25.00
Stock options outstanding (in shares)	77
Stock options outstanding, weighted-average remaining contractual life	1 year 8 months 5 days
Stock options outstanding, weighted-average exercise price per share	$ 22.84
Stock options outstanding, aggregate intrinsic value	10
Stock options exercisable (in shares)	77
Stock options exercisable, weighted-average exercise price per share	$ 22.84
Stock options exercisable, aggregate intrinsic value	10
$25.01 - 35.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range of exercise price of stock options outstanding and exercisable, minimum	$ 25.01
Range of exercise price of stock options outstanding and exercisable, maximum	$ 35.00
Stock options outstanding (in shares)	108
Stock options outstanding, weighted-average remaining contractual life	2 years 5 months 5 days
Stock options outstanding, weighted-average exercise price per share	$ 30.69
Stock options outstanding, aggregate intrinsic value	0
Stock options exercisable (in shares)	108
Stock options exercisable, weighted-average exercise price per share	$ 30.69
Stock options exercisable, aggregate intrinsic value	$ 0