Equity Based Compensation (Summary Of Information Concerning Outstanding And Exercisable Options) (Details) - $ / shares	6 Months Ended
Jan. 31, 2017	Jul. 31, 2016
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding (in shares)	7,145,005	6,822,390
Weighted Average Remaining Contractual Life (Years)	5 years 10 months 28 days
Weighted Average Exercise Price of Outstanding Options (in usd per share)	$ 32.10
Number Exercisable (in shares)	5,326,579
Weighted Average Exercise Price of Exercisable Options (in usd per share)	$ 30.43
$ 0.00 to $17.69
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, lower range (in usd per share)	0
Range of Exercise Prices, upper range (in usd per share)	$ 17.69
Number Outstanding (in shares)	475,245
Weighted Average Remaining Contractual Life (Years)	1 year 10 months 28 days
Weighted Average Exercise Price of Outstanding Options (in usd per share)	$ 17.05
Number Exercisable (in shares)	475,245
Weighted Average Exercise Price of Exercisable Options (in usd per share)	$ 17.05
$17.70 to $23.69
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, lower range (in usd per share)	17.70
Range of Exercise Prices, upper range (in usd per share)	$ 23.69
Number Outstanding (in shares)	1,173,588
Weighted Average Remaining Contractual Life (Years)	2 years 2 months 1 day
Weighted Average Exercise Price of Outstanding Options (in usd per share)	$ 21.44
Number Exercisable (in shares)	1,173,588
Weighted Average Exercise Price of Exercisable Options (in usd per share)	$ 21.44
$23.70 to $29.69
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, lower range (in usd per share)	23.70
Range of Exercise Prices, upper range (in usd per share)	$ 29.69
Number Outstanding (in shares)	1,584,597
Weighted Average Remaining Contractual Life (Years)	6 years 8 months 12 days
Weighted Average Exercise Price of Outstanding Options (in usd per share)	$ 28.54
Number Exercisable (in shares)	985,194
Weighted Average Exercise Price of Exercisable Options (in usd per share)	$ 28.83
$29.70 to $35.69
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, lower range (in usd per share)	29.70
Range of Exercise Prices, upper range (in usd per share)	$ 35.69
Number Outstanding (in shares)	1,432,395
Weighted Average Remaining Contractual Life (Years)	5 years 4 months 6 days
Weighted Average Exercise Price of Outstanding Options (in usd per share)	$ 34.22
Number Exercisable (in shares)	1,406,129
Weighted Average Exercise Price of Exercisable Options (in usd per share)	$ 34.27
$35.70 and above
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, lower range (in usd per share)	$ 35.70
Number Outstanding (in shares)	2,479,180
Weighted Average Remaining Contractual Life (Years)	8 years 3 months 7 days
Weighted Average Exercise Price of Outstanding Options (in usd per share)	$ 41.08
Number Exercisable (in shares)	1,286,423
Weighted Average Exercise Price of Exercisable Options (in usd per share)	$ 40.59

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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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-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
-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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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
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-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 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.

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