Note 15 - 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, 2019	Dec. 31, 2018
Beginning Balance	$ 95,692
Ending Balance	101,066	$ 95,692
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member]
Beginning Balance	(8,190)	(6,492)
Other Comprehensive Income Before Reclassification	3,163	(1,607)
Amounts Reclassified from Accumulated Other Comprehensive Income		(91)
Change in Unrealized Gains (Losses) on Securities Available for Sale, Net of Reclassification Adjustment and Tax Effects	3,163	(1,698)
Ending Balance	$ (5,027)	$ (8,190)

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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