Note 14 - Accumulated Other Comprehensive Income (Loss) - Changes for Unrealized Gains and Losses Securities Available for Sale (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2018	Dec. 31, 2017
Beginning Balance	$ 90,323
Ending Balance	89,966	$ 90,323
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Beginning Balance	(6,491)	(5,022)
Other Comprehensive Income Before Reclassification	(3,124)	(401)
Amounts Reclassified from Accumulated Other Comprehensive Income
TCJ Act		(1,068)
Change in Unrealized Gains (Losses) on Securities Available for Sale, Net of Reclassification Adjustment and Tax Effects	(3,124)	(1,469)
Ending Balance	$ (9,615)	$ (6,491)

Represents the effect of tax rate changes on Other Comprehensive Income (Loss) during the period.

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Amount after tax, before reclassification adjustments, of other comprehensive income (loss), attributable to parent.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Amount after tax of reclassification adjustments of other comprehensive income (loss) attributable to parent.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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