Represents the number of executives.

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- Definition

Represents the percentage of the maximum shares for the target number of shares awarded.

+ References

No definition available.

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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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The period of monthly closing prices used for the estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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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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- Definition

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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- Definition

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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- Definition

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

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

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- Definition

Percentage of vesting of share-based compensation awards.

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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	1 Months Ended		3 Months Ended			12 Months Ended	13 Months Ended
	Apr. 30, 2020 USD ($) person shares	Apr. 30, 2019 person	Apr. 30, 2020 USD ($) shares	Apr. 30, 2019 USD ($) shares	Apr. 30, 2018 shares	Apr. 30, 2020 USD ($) shares	Apr. 30, 2020 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award
Percentage reduction in the aggregate fair value of stock option			88.50%
Stock compensation expense			$ 642	$ 413
Unrecognized compensation cost	$ 3,600		3,600			$ 3,600	$ 3,600
Intrinsic value of outstanding stock options	2,700		2,700			2,700	2,700
Intrinsic value of exercisable stock options	$ 3,400		$ 3,400			$ 3,400	$ 3,400
Period used for calculations			5 years
Minimum
Share-based Compensation Arrangement by Share-based Payment Award
Period used for calculations			3 years
Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Period used for calculations			5 years
2011 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares of common stock available for award \| shares	166,999		166,999			166,999	166,999
2020 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares of common stock reserved for issuance \| shares	500,000		500,000			500,000	500,000
Stock Options Plans
Share-based Compensation Arrangement by Share-based Payment Award
Compensation expense recognize, period			3 years
Intrinsic value of the stock options exercised			$ 300	$ 1,400
Stock Options Plans \| 2011 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Initial vesting percentage			33.33%
Period to become exercisable			3 years
Number of shares of common stock reserved for issuance \| shares	1,700,000		1,700,000			1,700,000	1,700,000
ISOs \| 2011 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 \| 2011 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Period to become exercisable		3 years				3 years	3 years
Number of executives \| person	2	2
Percentage of the maximum shares for the target number of shares awarded			50.00%
Senior executives \| Performance-based restricted stock units \| 2011 Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares awarded \| shares			45,000	36,000	36,000