Note 7 - Securities Available for Sale - Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Due less than one year, amortized cost	$ 46,906
Due less than one year, fair value	47,594
Due after one year through five years, amortized cost	37,624
Due after one year through five years, fair value	38,539
Due after five years through ten years, amortized cost	13,469
Due after five years through ten years, fair value	13,863
Due after ten years, amortized cost	1,106
Due after ten years, fair value	943
Total, amortized cost	99,105	$ 107,528
Total, fair value	$ 100,939	$ 107,592

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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