Stock-based Compensation (Schedule Of Stock Option Activity) (Details) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	9 Months Ended
May 03, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Beginning of year, Options	408
Granted, Options	0
Exercised, Options	(310)
Terminated, Options	(3)
End of year, Options	95
Exercisable at end of period, Options	95
Beginning of period, Weighted-Average Exercise Price	$ 28.33
Granted, Weighted-Average Exercise Price	$ 0.00
Exercised, Weighted-Average Exercise Price	$ 27.85
Terminated, Weighted-Average Exercise Price	$ 26.36
End of period, Weighted-Average Exercise Price	$ 29.91
Exercisable at end of period, Weighted-Average Exercise Price	$ 29.91
Outstanding at end of period, Weighted-Average Remaining Contractual Life (In years)	8 months
Exercisable at end of period, Weighted-Average Remaining Contractual Life (In years)	8 months
Outstanding at end of period, Aggregate Intrinsic Value	$ 1
Exercisable at end of period, Aggregate Intrinsic Value	$ 1

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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.

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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.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

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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.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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- Definition

Gross number of share options (or share units) granted during the period.

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

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

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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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.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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