Unrecognized cost of not currently expected to vest share-based compensation awards.

No definition available.

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- Definition

Represents the number of options exercised through net settlements during the period in accordance with plan provisions.

+ References

No definition available.

+ Details

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- Definition

Represents the number of options exercised through net settlements during the period in accordance with plan provisions, net of shares to satisfy the exercise price and applicable withholding taxes.

+ References

No definition available.

+ Details

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- Definition

The grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

No definition available.

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- Definition

With regard to stock options, this element represents the reduction in shares issued during the period to satisfy the exercise price and applicable withholding taxes.

+ References

No definition available.

+ Details

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- Definition

As of the balance sheet date, the number of shares into which not currently expected to vest stock options outstanding can be converted under the option plan.

+ References

No definition available.

+ Details

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- Definition

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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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- Definition

The amount of expense, net of income tax, 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.

+ References

No definition available.

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Period Type:	duration

- Definition

Aggregate number of common shares reserved for future issuance.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
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- Definition

Unrecognized cost of unvested share-based compensation awards.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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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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Period Type:	duration

- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ 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
-Subparagraph (c)(2)(iii)(1)
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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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-SubTopic 10
-Section 50
-Paragraph 2
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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 maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
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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

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-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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Period Type:	duration

- 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

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. 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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-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(2)
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- Definition

Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. 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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- Definition

Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest exercisable or convertible options. 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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-SubTopic 10
-Section 50
-Paragraph 2
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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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Weighted average remaining contractual term for fully vested and expected to vest exercisable or convertible options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. 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.

+ References

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Note I - Stock-based Compensation (Details Textual) - USD ($)			1 Months Ended		9 Months Ended
	Aug. 29, 2018	Aug. 05, 2015	Aug. 31, 2015	May 31, 2015	Jan. 31, 2019	Jan. 31, 2018
Allocated Share-based Compensation Expense, Total					$ 2,300,000	$ 1,300,000
Allocated Share-based Compensation Expense, Net of Tax					$ 1,800,000	$ 843,000
Share-based Compensation Arrangement by Share-based Payment Award, Options Exercised Through Net Settlements					88,750	57,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Reduction in Shares Issued to Satisfy the Exercise Price and Applicable Withholding Taxes					42,617	36,171
Share-based Compensation Arrangement by Share-based Payment Award, Options Exercised Through Net Settlements, Net of Shares to Satisfy the Exercise Price and Applicable Withholding Taxes					46,133	20,829
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value					$ 15,200,000	$ 10,900,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number					187,500
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Aggregate Intrinsic Value					$ 6,300,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Remaining Contractual Term					3 years 146 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Exercise Price					$ 36.36
Employee Stock Option [Member]
Allocated Share-based Compensation Expense, Total					$ 1,500,000	1,000,000
Allocated Share-based Compensation Expense, Net of Tax					$ 1,200,000	$ 670,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross					145,000	25,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Grant Date Fair Value					$ 3,000,000	$ 336,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Total					$ 3,200,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition					2 years 109 days
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross			40,000	91,125
Employee Service Share-based Compensation, Not Currently Expected to Vest Awards, Compensation Cost Not yet Recognized					$ 1,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Not Currently Expected to Vest, Outstanding, Number					61,000
Restated Option Plan [Member]
Common Stock, Capital Shares Reserved for Future Issuance		1,800,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized	200,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	2,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant					298,500
Restated Option Plan [Member] \| Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period		10 years
Stock Incentive Plan [Member]
Allocated Share-based Compensation Expense, Total					$ 756,000	241,000
Allocated Share-based Compensation Expense, Net of Tax					575,000	$ 161,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized	100,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	450,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Total					$ 6,900,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition					7 years 146 days
Stock Incentive Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period					3,000	34,500
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant					106,527
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance					180,500
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value					$ 46.16