Stockholder's Equity (Details 4) (Stock Options, USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Jul. 31, 2013
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number Outstanding at July 31, 2013	14,922
Weighted-Average Remaining Contractual Life	5 years 10 months 28 days
Weighted- Average Exercise Price, Options Outstanding	$ 16.75
Number Exercisable at July 31, 2013	11,526
Weighted-Average Exercise Price, Options Exercisable	$ 16.03
Excercise price $9.00-$14.88
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Limit	$ 9.00
Range of Exercise Prices, Upper Limit	$ 14.88
Number Outstanding at July 31, 2013	774
Weighted-Average Remaining Contractual Life	2 years 10 months 24 days
Weighted- Average Exercise Price, Options Outstanding	$ 12.30
Number Exercisable at July 31, 2013	774
Weighted-Average Exercise Price, Options Exercisable	$ 12.30
Excercise price $15.11-$15.11
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Limit	$ 15.11
Range of Exercise Prices, Upper Limit	$ 15.11
Number Outstanding at July 31, 2013	8,000
Weighted-Average Remaining Contractual Life	5 years 8 months 12 days
Weighted- Average Exercise Price, Options Outstanding	$ 15.11
Number Exercisable at July 31, 2013	6,800
Weighted-Average Exercise Price, Options Exercisable	$ 15.11
Excercise price $16.38-$20.56
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Limit	$ 16.38
Range of Exercise Prices, Upper Limit	$ 20.56
Number Outstanding at July 31, 2013	5,063
Weighted-Average Remaining Contractual Life	6 years 1 month 10 days
Weighted- Average Exercise Price, Options Outstanding	$ 18.28
Number Exercisable at July 31, 2013	3,666
Weighted-Average Exercise Price, Options Exercisable	$ 17.99
Excercise price $21.05-$35.72
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of Exercise Prices, Lower Limit	$ 21.05
Range of Exercise Prices, Upper Limit	$ 35.72
Number Outstanding at July 31, 2013	1,085
Weighted-Average Remaining Contractual Life	8 years 7 months 24 days
Weighted- Average Exercise Price, Options Outstanding	$ 25.03
Number Exercisable at July 31, 2013	286
Weighted-Average Exercise Price, Options Exercisable	$ 22.85

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

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 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 number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ 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)(iii)

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

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans 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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- Definition

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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- Definition

Weighted average remaining contractual term of outstanding stock options, 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 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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