Number of anniversaries.

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Represents the number of executives.

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

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

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The number of issues 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 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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Aggregate number of common shares reserved for future issuance.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of noncash expense for share-based payment arrangement.

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

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

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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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Description of terms of award under share-based payment arrangement.

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Percentage of vesting of award under share-based payment arrangement.

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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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Purchase price of common stock expressed as a percentage of its fair value.

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STOCK-BASED COMPENSATION - Additional Information (Details) $ in Thousands	1 Months Ended		3 Months Ended
	Apr. 30, 2021 USD ($) person item shares	Apr. 30, 2020 person shares	Apr. 30, 2021 USD ($) item shares	Apr. 30, 2020 USD ($)	Jun. 23, 2020 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 \| $			$ 679	$ 642
Unrecognized compensation cost \| $	$ 7,400		$ 7,400
Compensation expense recognize, period			3 years
Intrinsic value of outstanding stock options \| $	12,500		$ 12,500
Intrinsic value of exercisable stock options \| $	$ 9,200		$ 9,200
Period used for calculations			5 years
Fair value of award as a percentage of market value			50.00%
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
2020 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares of common stock reserved for issuance					500,000
Stock Options Plans
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 available for award	493,528		493,528
Number of shares of common stock reserved for issuance	2,090,929		2,090,929
Intrinsic value of the stock options exercised \| $			$ 300	$ 300
Performance-based restricted stock units \| 2011 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number of executives \| person	4	2
ISOs/NSOs
Share-based Compensation Arrangement by Share-based Payment Award
Incentive stock option award maximum expiration period			10 years
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares earned and issue under the restricted stock unit			40,000
Restricted Stock Units \| 2011 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Period to become exercisable			3 years
Number of shares earned and issue under the restricted stock unit			40,471
Renewable Performance-Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Awards authorized	5,000		5,000
Share-based Compensation Arrangement by Share-based Payment Award, Terms of Award	three-year
Time Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Initial vesting percentage	33.33%
Awards authorized	49,500		49,500
Number of anniversaries \| item	3		3
Senior executives \| Performance-based restricted stock units \| 2011 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Period to become exercisable			3 years
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		45,000	49,000
Senior executives \| Renewable Performance-Based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Number of executives \| person	2