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

No definition available.

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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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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.

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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.

+ References

Reference 1: 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.F)
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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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- 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)
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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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 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).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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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- 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.

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- Definition

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

+ References

No definition available.

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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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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Paragraph 2
-Subparagraph (e)(2)
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 2
-Subparagraph (e)(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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

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Note I - Stock-based Compensation (Details Textual) - USD ($)		1 Months Ended		9 Months Ended		12 Months Ended	21 Months Ended
	Aug. 05, 2015	Aug. 31, 2015	May 31, 2015	Jan. 31, 2018	Jan. 31, 2017	Apr. 30, 2017	Jan. 31, 2018	Oct. 14, 2009
Allocated Share-based Compensation Expense				$ 1,258,000	$ 1,000,000
Allocated Share-based Compensation Expense, Net of Tax				$ 843,000	627,000
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent				33.00%		35.00%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value				$ 10,900,000	13,700,000		$ 10,900,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number				552,500			552,500
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Aggregate Intrinsic Value				$ 9,900,000			$ 9,900,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Remaining Contractual Term				2 years 153 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Exercise Price				$ 28.38			$ 28.38
Employee Stock Option [Member]
Allocated Share-based Compensation Expense				$ 1,000,000	923,000
Allocated Share-based Compensation Expense, Net of Tax				$ 670,000	$ 579,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				25,000	35,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Grant Date Fair Value				$ 336,000	$ 338,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized				1,900,000			$ 1,900,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition							2 years 73 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				$ 1,100,000			$ 1,100,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Not Currently Expected to Vest, Outstanding, Number				62,750			62,750
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period				34,500	10,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant				139,027			139,027
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number				48,000			48,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value				$ 38.18
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 Shares Available for Grant				288,000			288,000
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				$ 241,000	$ 78,000
Allocated Share-based Compensation Expense, Net of Tax				161,000	$ 49,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized				$ 1,400,000			$ 1,400,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition				3 years 328 days
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized								350,000