Represents the number of executives.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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.

+ References

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

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

+ References

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
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- Definition

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.

+ References

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STOCK-BASED COMPENSATION - Additional Information (Details) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended		11 Months Ended
	Apr. 30, 2018 person shares	Oct. 31, 2018 USD ($) shares	Oct. 31, 2017 USD ($)	Oct. 31, 2018 USD ($) shares	Oct. 31, 2017 USD ($)	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award
Stock compensation expense		$ 300	$ 1,300	$ 1,244	$ 3,573
Unrecognized compensation cost		3,600		3,600
Intrinsic value of outstanding stock options		7,100		7,100
Intrinsic value of exercisable stock options		$ 6,400		$ 6,400
Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares of common stock available for award \| shares		675,500		675,500
Stock Options Plans
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares of common stock reserved for issuance \| shares		1,800,000		1,800,000
Compensation expense recognize, period				3 years
Intrinsic value of the stock options exercised				$ 100	$ 3,100
Stock Options Plans \| Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award
Period to become exercisable				3 years		1 year
ISOs \| Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award
Incentive stock option award maximum expiration period				10 years
NSOs \| Stock 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 \| Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number of executives \| person	2
Period to become exercisable	3 years
Senior executives \| Performance-based restricted stock units \| Stock Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares awarded \| shares	36,000