2000 Stock Incentive Plan [Abstract]

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- Definition

2001 Employee Stock Purchase Plan [Abstract]

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The aggregate number of expired and canceled stock-based awards under stock option plan.

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No definition available.

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The aggregate number of stock-based awards granted, net of expired and canceled awards.

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No definition available.

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- Definition

Discount rate from market value, on purchase date, offered to employees participating in the Employee Stock Purchase Plan (ESPP)

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No definition available.

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The maximum term for grants of incentive and non-qualified stock-based awards, excluding grants of incentive stock-based awards to stockholders who own more than 10% of the voting power.

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No definition available.

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The maximum term for grants of incentive stock-based awards granted to a stockholder who owns more than 10% of the voting power.

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No definition available.

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The number of stock based awards exercised or converted into shares, other instruments, or cash in accordance with the terms of the arrangement as of the balance sheet date.

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No definition available.

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The number of shares reserved for issuance under stock-based award agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested stock-based awards.

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No definition available.

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Percentage of a stockholder's voting power that limits the contractual term of an incentive stock-based award.

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- Definition

Stock-Based Awards Outstanding By Award Type (In Shares) [Abstract]

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Total number of shares of common stock issued to employees under employee stock purchase plan and through the end of the reporting period

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No definition available.

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ 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

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

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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- Definition

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

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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

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-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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Stock-Based Compensation - Overview (Details) - shares	9 Months Ended
Stock-Based Compensation - Overview (Details) - shares	Apr. 30, 2016	Jan. 31, 2016	Dec. 31, 2015	Oct. 31, 2015	Jul. 31, 2015
Stock options
Stock-Based Awards Outstanding By Award Type (In Shares)
Number of stock-based option awards outstanding at period end	2,362,198	2,350,258		2,398,498	2,119,683
2000 Stock Incentive Plan
2000 Stock Incentive Plan
Aggregate maximum number of shares of common stock which may be issued under stock option plan	8,962,500
Aggregate net number of stock-based awards granted	7,737,852
Aggregate number of stock based awards expired and canceled	3,157,309
Aggregate number of stock-based awards exercised	5,143,687
Stock-Based Awards Outstanding By Award Type (In Shares)
Number of total stock-based awards outstanding	2,594,165
2000 Stock Incentive Plan \| Stock options
2000 Stock Incentive Plan
Maximum term for grants of incentive and non-qualified stock-based awards, excluding incentive stock-based awards granted to stockholders who own more than 10% of the voting power	10 years
Percentage of a stockholder's voting power that limits the contractual term of an incentive stock-based award	10.00%
Maximum term for incentive stock-based awards granted to stockholders who own more than 10% of the voting power	5 years
Stock-Based Awards Outstanding By Award Type (In Shares)
Number of stock-based option awards outstanding at period end	2,362,198
2000 Stock Incentive Plan \| Performance shares
Stock-Based Awards Outstanding By Award Type (In Shares)
Number of stock-based non-option awards outstanding at period end	183,665
2000 Stock Incentive Plan \| RSUs and restricted stock
Stock-Based Awards Outstanding By Award Type (In Shares)
Number of stock-based non-option awards outstanding at period end	39,799
2000 Stock Incentive Plan \| Share units
Stock-Based Awards Outstanding By Award Type (In Shares)
Number of stock-based non-option awards outstanding at period end	8,503
2001 Employee Stock Purchase Plan \| Employee Stock Purchase Plan - ESPP
2000 Stock Incentive Plan
Aggregate maximum number of shares of common stock which may be issued under stock option plan	800,000		675,000
2001 Employee Stock Purchase Plan
Discount rate from market value, on purchase date, offered to employees participating in the Employee Stock Purchase Plan (ESPP)	85.00%
Total number of shares of common stock issued to employees under employee stock purchase plan and through the end of the reporting period	618,123