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

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No definition available.

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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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=116856206&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)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Number of shares authorized for issuance under share-based payment arrangement.

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock-Based Compensation - Overview (Details) - shares	9 Months Ended
Stock-Based Compensation - Overview (Details) - shares	Apr. 30, 2020	Jan. 31, 2020	Oct. 31, 2019	Jul. 31, 2019
Stock options
Stock-Based Awards Outstanding By Award Type
Number of stock-based option awards outstanding at period end (in shares)	1,139,675	1,269,865	1,503,295	1,555,555
2000 Stock Incentive Plan
2000 Stock Incentive Plan
Authorized for issuance (in shares)	10,962,500
Aggregate net number of stock-based awards granted (in shares)	8,568,523
Aggregate number of stock based awards expired and canceled (in shares)	4,191,578
Aggregate number of stock-based awards exercised or settled (in shares)	6,525,623
Stock-Based Awards Outstanding By Award Type
Number of total stock-based awards outstanding (in shares)	2,042,900
2000 Stock Incentive Plan \| Stock options
2000 Stock Incentive Plan
Contractual term	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
Number of stock-based option awards outstanding at period end (in shares)	1,139,675
2000 Stock Incentive Plan \| Performance shares
Stock-Based Awards Outstanding By Award Type
Number of stock-based non-option awards outstanding at period end (in shares)	215,234
2000 Stock Incentive Plan \| RSUs and restricted stock
Stock-Based Awards Outstanding By Award Type
Number of stock-based non-option awards outstanding at period end (in shares)	448,311
2000 Stock Incentive Plan \| Share units
Stock-Based Awards Outstanding By Award Type
Number of stock-based non-option awards outstanding at period end (in shares)	239,680
2001 Employee Stock Purchase Plan \| ESPP
2000 Stock Incentive Plan
Authorized for issuance (in shares)	1,050,000
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 (in shares)	823,219