Note 4 - Earnings Per Share & Share Repurchase Plan (Details Textual) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Earnings Per Share and Share Repurchase Plan [Line Items]
Treasury Stock, Shares	164,569		164,569
Treasury Stock, Value	$ 2,476		$ 2,476
Share Repurchase Program 1 [Member]
Earnings Per Share and Share Repurchase Plan [Line Items]
Stock Repurchase Program, Number of Shares Authorized to be Repurchased	100,000
Treasury Stock, Shares, Acquired	0	0
Treasury Stock, Shares	57,883
Treasury Stock Shares Average Price Per Share Acquired	$ 16.97
Treasury Stock, Value	$ 982
Employee Stock Option [Member]
Earnings Per Share and Share Repurchase Plan [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	74,150	25,000

Earnings per share and share repurchase plan.

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- Definition

Represents the average cost per share of the total shares acquired.

+ References

No definition available.

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

+ References

No definition available.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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Number of shares that have been repurchased during the period and are being held in treasury.

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The amount allocated to treasury stock. Treasury stock is common and preferred shares of an entity that were issued, repurchased by the entity, and are held in its treasury.

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