Represents the number of executives.

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- Definition

Represents the percentage reduction in the aggregate fair value of stock option

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No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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No definition available.

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- Definition

Net number of non-option equity instruments granted to participants.

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

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

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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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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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STOCK-BASED COMPENSATION - Additional Information (Details) $ in Thousands	3 Months Ended		6 Months Ended		11 Months Ended
	Apr. 30, 2019 person shares	Apr. 30, 2018 person shares	Jul. 31, 2019 USD ($) shares	Jul. 31, 2018 USD ($)	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award
Period to become exercisable			3 years
Percentage reduction in the aggregate fair value of stock option			88.50%
Stock compensation expense			$ 926	$ 906
Unrecognized compensation cost			4,400
Intrinsic value of outstanding stock options			4,500
Intrinsic value of exercisable stock options			$ 4,200
Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares of common stock available for award \| shares			520,000
Stock Options Plans
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares of common stock reserved for issuance \| shares			1,700,000
Compensation expense recognize, period			3 years
Intrinsic value of the stock options exercised			$ 1,400
Stock Options Plans \| Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award
Period to become exercisable			3 years		1 year
ISOs \| Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award
Incentive stock option award maximum expiration period			10 years
NSOs \| Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award
Incentive stock option award maximum expiration period			10 years
Senior executives \| Performance-based restricted stock units \| Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award
Period to become exercisable	3 years	3 years
Number of executives \| person	2	2
Senior executives \| Performance-based restricted stock units \| Stock Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares awarded \| shares	36,000	36,000