Stock-Based Compensation Overview (Details)	3 Months Ended
Oct. 31, 2013
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
Maximum term for incentive stock-based awards granted to stockholders who own more than 10% of the voting power	5 years
Percentage of a stockholder's voting power that limits the contractual term of an incentive stock-based award	10.00%
Aggregate net number of stock-based awards granted	6,874,264
Aggregate number of stock based awards expired and canceled	2,695,240
Aggregate number of stock-based awards exercised	3,830,652
Stock-Based Awards Outstanding By Award Type (In Shares)
Number of total stock-based awards outstanding	3,043,612
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
Stock-Based Awards Outstanding By Award Type (In Shares)
Number of stock-based awards outstanding at period end	2,870,620
2000 Stock Incentive Plan \| Performance shares
Stock-Based Awards Outstanding By Award Type (In Shares)
Number of stock-based awards outstanding at period end	121,986
2000 Stock Incentive Plan \| RSUs and restricted stock
Stock-Based Awards Outstanding By Award Type (In Shares)
Number of stock-based awards outstanding at period end	37,326
2000 Stock Incentive Plan \| Share units
Stock-Based Awards Outstanding By Award Type (In Shares)
Number of stock-based awards outstanding at period end	6,680
2000 Stock Incentive Plan \| SARs
Stock-Based Awards Outstanding By Award Type (In Shares)
Number of stock-based awards outstanding at period end	7,000
2001 Employee Stock Purchase Plan
2001 Employee Stock Purchase Plan
Total number of common shares reserved for issuance under employee stock purchase plan	675,000
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	526,517

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- Definition

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

+ References

No definition available.

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- Definition

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.

+ References

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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- Definition

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.

+ References

No definition available.

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- Definition

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

+ References

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.

+ References

No definition available.

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- Definition

Number of shares of common stock that were reserved for issuance under the Employee Stock Purchase Plan.

+ References

No definition available.

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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 shares reserved for issuance under non-option equity instrument agreements awarded that validly exist and are outstanding, including vested instruments.

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

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