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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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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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STOCK-BASED COMPENSATION - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 31, 2024	Jul. 31, 2023	Jul. 31, 2024	Jul. 31, 2023
Share-based Compensation Arrangement by Share-based Payment Award
Stock compensation expense	$ 1,000	$ 1,200	$ 2,215	$ 2,218
Unrecognized compensation cost	6,800		$ 6,800
Compensation expense recognize, period			3 years
Intrinsic value of the stock options exercised			$ 17,100	$ 900
Intrinsic value of outstanding stock options	23,000		23,000
Intrinsic value of exercisable stock options	$ 20,200		$ 20,200
Cash dividends deemed paid on shares			2,738
Stock Plans
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares of common stock reserved for issuance	1,540,667		1,540,667
Number of shares of common stock available for award	488,799		488,799
Performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award
The number of shares issuable under restricted stock units awarded during the period	5,000		5,000
Earnings per share performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award
The number of shares issuable under restricted stock units awarded during the period	10,000		10,000
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award
Incentive stock option award maximum expiration period			3 years
Renewable energy performance-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award
The number of shares issuable under restricted stock units awarded during the period	5,000		5,000
Time-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award
The number of shares issuable under restricted stock units awarded during the period	39,050		39,050