Note 17 - Shareholders' Equity and Stock Plans - Additional Compensation Information (Details) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Number of exercisable shares (in shares)	93,400
Number of shares granted (in shares)	4,653	4,868
Grant price (in dollars per share)	$ 11.50	$ 10.05
Compensation expense	$ 53,510	$ 48,923
Employee Stock Option [Member]
Stock compensation expense	8,000	23,000	$ 24,000
Unrecognized compensation costs related to non-vested stock option payments		$ 17,000	$ 29,000
Number of exercisable shares (in shares)	93,000	119,000	157,000
Restricted Stock [Member]
Stock compensation expense	$ 185,000	$ 196,000	$ 215,000
Restricted stock awards weighted average grant date fair value per share (in dollars per share)	$ 11.50	$ 10.35	$ 5.74
Unrecognized compensation costs related to non-vested restricted stock payments	$ 470,000	$ 414,000	$ 205,000

The weighted average grant-date price of common stock shares granted during the reporting period.

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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 awards, other than options, awarded to employees as compensation.

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Unrecognized cost of unvested options awarded to employees as compensation.

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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 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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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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Gross number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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