Accounting For Stock-Based Compensation (Summary Of Information Concerning Outstanding And Exercisable Options) (Details) (USD $)	6 Months Ended
Jan. 31, 2015	Jul. 31, 2014
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding	7,573,315	7,197,882
Weighted Average Remaining Contractual Life (Years)	5 years 10 months 24 days
Weighted Average Exercise Price	$ 29.08
Number Exercisable	5,756,328
Weighted Average Exercise Price	$ 25.95
Range Of Exercise Prices $0.00 To $17.69 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, lower range	$ 0.00
Range of Exercise Prices, upper range	$ 17.69
Number Outstanding	1,571,174
Weighted Average Remaining Contractual Life (Years)	2 years 3 months 15 days
Weighted Average Exercise Price	$ 17.01
Number Exercisable	1,571,174
Weighted Average Exercise Price	$ 17.01
Range Of Exercise Prices $17.70 To $23.69 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, lower range	$ 17.70
Range of Exercise Prices, upper range	$ 23.69
Number Outstanding	1,488,345
Weighted Average Remaining Contractual Life (Years)	4 years 7 days
Weighted Average Exercise Price	$ 21.44
Number Exercisable	1,488,345
Weighted Average Exercise Price	$ 21.44
Range Of Exercise Prices $23.70 To $29.69 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, lower range	$ 23.70
Range of Exercise Prices, upper range	$ 29.69
Number Outstanding	844,768
Weighted Average Remaining Contractual Life (Years)	5 years 10 months 2 days
Weighted Average Exercise Price	$ 29.12
Number Exercisable	844,768
Weighted Average Exercise Price	$ 29.12
Range Of Exercise Prices $29.70 To $35.69 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, lower range	$ 29.70
Range of Exercise Prices, upper range	$ 35.69
Number Outstanding	1,778,353
Weighted Average Remaining Contractual Life (Years)	7 years 2 months 12 days
Weighted Average Exercise Price	$ 34.23
Number Exercisable	1,506,618
Weighted Average Exercise Price	$ 34.32
Range Of Exercise Prices $35.70 And Above [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, lower range	$ 35.70
Number Outstanding	1,890,675
Weighted Average Remaining Contractual Life (Years)	9 years 2 months 5 days
Weighted Average Exercise Price	$ 40.26
Number Exercisable	345,423
Weighted Average Exercise Price	$ 41.78

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.

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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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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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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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

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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

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The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ 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)-(ii)

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

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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

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-Name Accounting Standards Codification

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