Note 7 - Securities Available for Sale - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Due less than one year, amortized cost	$ 1,844
Due less than one year, fair value	1,777
Due after one year through five years, amortized cost	76,425
Due after one year through five years, fair value	74,370
Due after five years through ten years, amortized cost	2,767
Due after five years through ten years, fair value	2,643
Due after ten years, amortized cost	780
Due after ten years, fair value	670
No stated maturity, amortized cost	144
No stated maturity, fair value	144
Total, amortized cost	81,960	$ 78,801
Total, fair value	$ 79,604	$ 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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