Represents the incremental amount of shares to vest annually.

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Represents the minimum closing price per share to release shares expected to vest.

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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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Aggregate number of common shares reserved for future issuance.

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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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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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No definition available.

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Unrecognized cost of unvested options awarded to employees as compensation.

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

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No definition available.

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

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

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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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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Number of options vested.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Note 8 - Shareholders' Equity (Details Textual) - USD ($)			1 Months Ended	12 Months Ended
	Jan. 03, 2011	Dec. 30, 2010	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Jun. 30, 2004
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number				2,323,581	2,257,969	2,056,122
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				369,550	411,250
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price				$ 4.69	$ 4.68
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options				$ 505,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition				1 year 36 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value				$ 2.01	$ 2.32
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value				$ 149,000	$ 364,000
Proceeds from Stock Options Exercised				460,000	538,000
Excess Tax Benefit from Share-based Compensation, Financing Activities				0	0
Allocated Share-based Compensation Expense				$ 710,000	$ 571,000
Common Stock, Capital Shares Reserved for Future Issuance				901,700
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period				0	0
Allocated Share-based Compensation Expense				$ 34,000	$ 82,000
Restricted Stock [Member]
Allocated Share-based Compensation Expense				34,000	$ 82
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares			15,900
Stock Repurchased During Period, Shares			4,131
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options				$ 11,000
2004 Long-term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized				2,900,000			750,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number				1,243,697
2004 Long-term Incentive Plan [Member] \| President [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	50,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price	$ 6.58
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Incremental Vesting Shares	12,500
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	4 years
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period		5 years
2004 Long-term Incentive Plan [Member] \| Options I [Member] \| President [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		50,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price		$ 6.42
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Incremental Vesting Shares		12,500
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		4 years
2004 Long-term Incentive Plan [Member] \| Options II [Member] \| President [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		250,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price		$ 6.42
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Incremental Vesting Shares		62,500
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		4 years
2004 Long-term Incentive Plan [Member] \| Options III [Member] \| President [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		200,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price		$ 10
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Incremental Vesting Shares		50,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		4 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Minimum Closing Share Price		$ 10
2004 Long-term Incentive Plan [Member] \| Options IV [Member] \| President [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		200,000
Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price		$ 15
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Incremental Vesting Shares		50,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period		4 years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Minimum Closing Share Price		$ 15
2014 Long-term Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized				1,750,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number				679,884
2014 Long-term Incentive Plan [Member] \| Awards Other than Stock Options and SARs [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized				800,000
2014 Long-term Incentive Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period						3 years
Stock Issued During Period, Shares, Restricted Stock Award, Gross						49,200
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value						$ 3.24