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STOCK-BASED COMPENSATION - Additional Information (Details) $ in Thousands | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Apr. 30, 2020 person shares | Apr. 30, 2019 person shares | Apr. 30, 2018 person shares | Jan. 31, 2021 USD ($) shares | Jan. 31, 2020 USD ($) | Jan. 31, 2019 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% |  |  |
Percentage reduction in the aggregate fair value of stock option |  |  |  | 88.50% |  |  |
Stock compensation expense |  |  |  | $ 2,938 | $ 2,131 | $ 1,645 |
Unrecognized compensation cost |  |  |  | $ 3,600 |  |  |
Compensation expense recognize, period |  |  |  | 3 years |  |  |
Intrinsic value of outstanding stock options |  |  |  | $ 6,100 |  |  |
Intrinsic value of exercisable stock options |  |  |  | $ 4,100 |  |  |
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 |  |  |
2020 Plan |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |
Number of shares of common stock reserved for issuance | shares |  |  |  |  |  |  | 500,000
Stock Options Plans |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award |  |  |  |  |  |  |
Initial vesting percentage |  |  |  | 0.3333% |  |  |
Period to become exercisable |  |  |  | 3 years |  |  |
Number of shares of common stock available for award | shares |  |  |  | 634,832 |  |  |
Number of shares of common stock reserved for issuance | shares |  |  |  | 2,157,400 |  |  |
Intrinsic value of the stock options exercised |  |  |  | $ 1,500 | $ 1,400 | $ 200 |
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 shares of common stock available for award | shares | 45,000 | 36,000 | 36,000 |  |  |  |
Number of executives | person | 2 | 2 | 2 |  |  |  |
ISOs/NSOs |  |  |  |  |  |  |
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 |  |  |
Percentage of the maximum shares for the target number of shares awarded |  |  |  | 50.00% |  |  |

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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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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