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

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

The amount of change in stock option compensation expense during the period

+ References

No definition available.

+ Details

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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

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

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

+ Details

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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

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- Definition

For each plan, identification of the award pricing model or other valuation method used in calculating the weighted average fair values disclosed. The model is also used to calculate the compensation expense that is shown within the balance sheet, income statement, and cash flow. Examples of valuation techniques are lattice models (binomial model), closed-form models (Black-Scholes-Merton formula), and a Monte Carlo simulation technique. Fair value is the amount at which an asset or liability could be bought or incurred or sold or settled in a current transaction between willing parties, that is, other than in a forced or liquidation sale. May include disclosures about the assumptions underlying application of the method selected.

+ References

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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.

+ Details

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

+ Details

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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=6415400&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

+ Details

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- Definition

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

+ References

+ Details

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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

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- Definition

Expected term of share-based compensation awards, 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 (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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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

+ Details

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- Definition

The noncash expense that accounts for the value of stock or unit options distributed to employees as compensation.

+ 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 (b)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3602-108585

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STOCK-BASED COMPENSATION - Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended
	Jun. 22, 2017	Apr. 30, 2017	Apr. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award
Intrinsic value of outstanding stock options		$ 18,900
Intrinsic value of exercisable stock options		18,700
Compensation expense		$ 1,112	$ 659
Expected life (in years)		3 years 4 months 6 days	5 years 6 months
Reduction in the aggregate fair value of stock option		$ 1,200
Percentage reduction in the aggregate fair value of stock option		20.00%
Reduction in stock option compensation expense		$ 200
Stock Plan \| Forecast
Share-based Compensation Arrangement by Share-based Payment Award
Increase in number of shares of common stock reserved for issuance	750,000
Stock Options Plans
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares of common stock reserved for issuance		1,124,650
Intrinsic value of the stock options exercised		$ 1,000	$ 300
Compensation expense		$ 1,100	$ 700
Compensation expense recognize, period		12 months
Unrecognized compensation cost		$ 3,800
Method used for fair value assumption		Black-Scholes option-pricing model	Black-Scholes option-pricing model
Expected life (in years)		3 years 4 months 6 days	5 years 6 months
Stock Options Plans \| Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award
Number of shares of common stock available for award		340,000
ISOs \| Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award
Incentive stock option award maximum expiration period		10 years
Period to become exercisable		1 year
NSOs \| Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award
Incentive stock option award maximum expiration period		10 years
Period to become exercisable		1 year