Note 7 - Securities Available for Sale - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Due less than one year, amortized cost	$ 1,944
Due less than one year, fair value	1,909
Due after one year through five years, amortized cost	76,969
Due after one year through five years, fair value	75,306
Due after five years through ten years, amortized cost	3,211
Due after five years through ten years, fair value	3,146
Due after ten years, amortized cost	783
Due after ten years, fair value	639
No stated maturity, amortized cost	174
No stated maturity, fair value	174
Total, amortized cost	83,081	$ 78,801
Total, fair value	$ 81,174	$ 77,472

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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