Price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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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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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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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 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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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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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 share options (or share units) exercised during the current period.

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Note 6 - Equity-based Compensation (Details Textual)	9 Months Ended
Note 6 - Equity-based Compensation (Details Textual)	Sep. 30, 2018 USD ($) $ / shares shares	Sep. 30, 2017 USD ($) shares	Dec. 31, 2017 shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value \| $ / shares	$ 4.04
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period \| shares	15,464	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 89,000
Allocated Share-based Compensation Expense, Total	413,000	$ 0
Stock-based Compensation Expense [Member]
Allocated Share-based Compensation Expense, Total	306,000
Stock-based Other Noninterest Expense [Member]
Allocated Share-based Compensation Expense, Total	$ 107,000
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance \| shares	75,179		74,750
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period \| shares	429
Restricted Stock [Member] \| Incentive Plan [Member]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Total	$ 775,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	4 years 73 days
Employee Stock Option [Member] \| Incentive Plan [Member]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Total	$ 486,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	4 years 73 days
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Exercise Price	9.65
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Exercise Price	15.48