Allocated share based compensation expense net of tax amount per basic and diluted share.

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Average annual earnings percentage increase goal of share based compensation awards.

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Share based compensation arrangement by share based payment award annual percentage of award which vests.

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Share based compensation arrangement by share based payment award fair value assumptions expected forfeiture rate of unvested outstanding awards.

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Share based compensation arrangement by share based payment award number of shares reserved for issuance under awards outstanding.

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Sharebased compensation arrangement by share based payment awards annual service vesting percentage.

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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
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-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.

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- Definition

The amount of the cost recognized during the period for defined contribution plans.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of discretionary contributions made by an employer to a defined contribution plan.

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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Percentage employer matches of the employee's percentage contribution matched.

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Percentage of employer's matching contributions to a defined contribution plan that vests in a given year.

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No definition available.

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Maximum amount the employee may contribute to a defined contribution plan.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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.

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- Definition

Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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- Definition

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

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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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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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

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Number of options outstanding, including both vested and non-vested options.

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

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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 vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Value, before forfeitures, of stock or other type of equity granted of any equity-based compensation plan other than an employee stock ownership plan (ESOP).

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Note 11 - Employee Benefits (Details Textual) - USD ($)		1 Months Ended								12 Months Ended
Note 11 - Employee Benefits (Details Textual) - USD ($)	Dec. 31, 2016	Aug. 31, 2016	May 31, 2016	May 31, 2015	May 31, 2014	May 31, 2013	May 31, 2012	Aug. 31, 2011	Aug. 31, 2010	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted										304,251
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	800,000									800,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	553,750									553,750	850,184
Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Forfeiture Rate Of Unvested Outstanding Awards										1.25%
Allocated Share-based Compensation Expense										$ 883,000	$ 1,404,000	$ 921,000
Allocated Share-based Compensation Expense, Net of Tax										$ 547,000	$ 870,000	$ 571,000
Allocated Share Based Compensation Expense Net Of Tax Amount Per Basic And Diluted Share										$ 0.02	$ 0.03	$ 0.02
Excess Tax Benefit from Share-based Compensation, Financing Activities										$ 235,000	$ 432,000	$ 115,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term										4 years 36 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value	$ 2,800,000									$ 2,800,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number	287,100									287,100
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term										3 years 146 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value	$ 2,100,000									$ 2,100,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value										1,900,000	2,400,000	761,000
Proceeds from Stock Options Exercised	4,400,000										3,500,000	1,200,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value										$ 534,000	502,000	541,000
Defined Contribution Plan, Employer Matching Contribution, Percent of Match										35.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay										6.00%
Defined Contribution Plan, Employers Matching Contribution, Annual Vesting Percentage										20.00%
Defined Contribution Plan, Cost Recognized										$ 2,100,000	1,900,000	1,500,000
Defined Contribution Plan, Employer Discretionary Contribution Amount										0	0	0
Participants Less Than50 Years Old [Member]
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Amount										18,000
Participants Over50 Years Old [Member]
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Amount										$ 24,000
Employee Stock Option [Member] \| Awards Paid to Employees Upon Vesting [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted		1,000	13,000	19,500	11,000
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted									95,100
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period									5 years	5 years
Sharebased Compensation Arrangement By Share Based Payment Awards Annual Service Vesting Percentage									5.00%
Average Annual Earnings Percentage Increase Goal Of Share Based Compensation Awards									15.00%
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value										$ 247,000
Performance Shares [Member] \| One Half of Awards Paid Immediately Upon Vesting and One Half Credited to Employees' Accounts [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Granted			34,600	35,000	36,400	62,550	59,250	62,400
Unvested Service Based Option Awards [Member]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	1,300,000									$ 1,300,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition										3 years
Unvested Performance Unit Awards [Member]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 2,600,000									$ 2,600,000
Service Based Options [Member]
Stock Granted, Value, Share-based Compensation, Gross										$ 227,000	$ 918,000	$ 475,000
Two Thousand and Fifteen Plan [Member] \| Employee Stock Option [Member]
Share Based Compensation Arrangement By Share Based Payment Award Annual Percentage Of Award Which Vests										20.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period										1 year
Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Reserved For Issuance Under Awards Outstanding	192,000									192,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	553,750									553,750
Two Thousand and Fifteen Plan [Member] \| Performance Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Reserved For Issuance Under Awards Outstanding	94,671									94,671
Two Thousand And Five Plan [Member] \| Performance Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Reserved For Issuance Under Awards Outstanding	84,889									84,889
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	361,750									361,750
Minimum [Member] \| Two Thousand and Fifteen Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period										7 years
Maximum [Member] \| Two Thousand and Fifteen Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period										10 years