Stock Repurchases (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Oct. 31, 2018	Jan. 31, 2018
Share-Based Compensation Arrangement By Share-Based Payment Award, Options Exercisable [Abstract]
Options Exercised	62,000
Weighted Average Exercise Price	$ 19.93
Common Stock
Share-Based Compensation Arrangement By Share-Based Payment Award, Options Exercisable [Abstract]
Options Exercised		80,000
Weighted Average Exercise Price		$ 6.54
Shares Net Settled for Exercise		11,996
Shares Withheld for Taxes(1)		0
Net Shares to Individuals		68,004
Weighted Average Share Price for Withholding		$ 43.60
Employee Stock Based Tax Withholding (in 000s)		$ 0

No definition available.

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- Definition

Represents the number of net impact on number of shares settled resulting from exercise.

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No definition available.

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- Definition

Represents the number of shares withheld for taxes.

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- Definition

Amount of Tax Expenses Paid by Company releated to the Share-based Compensation to the taxing authority.

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The price per shares for withholding for taxes.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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- Definition

For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

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Number of share options (or share units) exercised during the current period.

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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
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