A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Number of shares related to Restricted Stock Award forfeited during the period.

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Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited.

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

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Stock-based Payment Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Oct. 31, 2020	Oct. 31, 2019	Jul. 31, 2020
Shares
Outstanding as of July 31, 2020	8,059,000
Grants of options (in shares)	350,000
Exercises (in shares)	(771,000)
Forfeitures or expirations (in shares)	(205,000)
Outstanding as of October 31, 2020	7,433,000		8,059,000
Exercisable as of October 31, 2020	4,217,000
Weighted Average Exercise Price
Outstanding as of July 31, 2019	$ 41.44
Grants of options (in dollars per share)	106.30
Exercises (in dollars per share)	25.97
Forfeitures (in dollars per share)	(47.53)
Outstanding as of January 31, 2020	45.93		$ 41.44
Exercisable as of January 31, 2020	$ 29.83
Weighted Average Remaining Contractual Term (In years)
Outstanding as of July 31, 2019			6 years 8 months 19 days
Outstanding as of October 31, 2020	6 years 9 months
Exercisable as of January 31, 2020	5 years 4 months 9 days
Aggregate Intrinsic Value
Outstanding as of July 31, 2019	$ 417,529
Outstanding as of January 31, 2020	478,932		$ 417,529
Exercisable as of October 31, 2020	$ 339,548
Restricted Shares
Outstanding as of July 31, 2020	105,000
Grants of restricted stock (in shares)	26,000
Vested restricted stock (in shares)	(13,000)
Forfeited restricted stock (in shares)	(5,000)
Outstanding as of October 31, 2020	113,000		105,000
Outstanding as of July 31, 2020, Weighted Average Grant Date Fair Value	$ 69.86
Granted restricted stock, Weighted Average Grant Date Fair Value	115.58
Vested restricted stock, Weighted Average Grant Date Fair Value	76.35
Forfeited restricted stock, Weighted Average Grant Date Fair Value	59.15
Outstanding as of October 31, 2020, Weighted Average Grant Date Fair Value	$ 79.80		$ 69.86
Total stock-based compensation	$ 8,913	$ 5,533
Restricted Stock [Member] \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	2 years
Restricted Shares
Award vesting period	2 years
Restricted Stock [Member] \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	5 years
Restricted Shares
Award vesting period	5 years