Represents stock repurchase program number of shares authorized to be repurchased under prior program.

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Stockholders Equity [Line Items]

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Unrecognized cost of unvested options awarded to employees as compensation.

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- Definition

The cash outflow to reacquire common stock during the period.

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Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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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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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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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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Gross number of share options (or share units) granted during the period.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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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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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of shares that have been repurchased during the period and are being held in treasury.

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STOCKHOLDERS' EQUITY - Textuals (Details) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2017
Stockholders Equity [Line Items]
Number of shares authorized to be repurchased under prior program	5,000,000
Common stock share acquired	723,072
Aggregate purchase price	$ 20,311
Granted	8,245	0	0
Dividend yield	0.00%
Proceeds from exercise of equity awards	$ 101	$ 1,578	$ 260
Share-based compensation expense	$ (19,694)	(19,665)	(16,901)
Long-Term Incentive Stock Plan
Stockholders Equity [Line Items]
Shares available for grant	717,381
Minimum
Stockholders Equity [Line Items]
Vesting and exercise period of awards	2 years
Maximum
Stockholders Equity [Line Items]
Vesting and exercise period of awards	5 years
Restricted Stock Units (RSUs) \| Long-Term Incentive Stock Plan
Stockholders Equity [Line Items]
Share-based compensation expense	$ 19,700	19,700	16,900
Unrecognized stock compensation related to unvested option awards	$ 19,400	23,000	40,700
Restricted Stock Units (RSUs) \| Minimum \| Long-Term Incentive Stock Plan
Stockholders Equity [Line Items]
Vesting and exercise period of awards	2 years
Restricted Stock Units (RSUs) \| Maximum \| Long-Term Incentive Stock Plan
Stockholders Equity [Line Items]
Vesting and exercise period of awards	5 years
Stock Options
Stockholders Equity [Line Items]
Weighted average remaining term for stock options outstanding	1 year 10 months 24 days
Aggregate intrinsic value for stock options outstanding	$ 1,100
Aggregate intrinsic value for stock option exercisable	1,000
Proceeds from exercise of equity awards	100	1,600
Intrinsic value of stock options exercised	400	3,600
Share-based compensation expense	$ 0	$ 0	$ 100
Stock Options \| Maximum
Stockholders Equity [Line Items]
Vesting and exercise period of awards	10 years