Note 3 - Securities - Maturity of Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Due in one year or less, amortized cost	$ 494
Due in one year or less, fair value	501
Due after one year through five years, amortized cost	2,296
Due after one year through five years, fair value	2,341
Due after five through ten years, amortized cost	17,091
Due after five through ten years, fair value	17,353
Due after ten years, amortized cost	37,969
Due after ten years, fair value	38,906
Securities available-for-sale, amortized cost	97,577	$ 120,245
Total securities available-for-sale	99,652	120,107
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities without maturity date, amortized cost	19,185
Securities without maturity date, fair value	19,692
Securities available-for-sale, amortized cost	19,185	40,868
Total securities available-for-sale	19,692	41,075
Collateralized Mortgage Obligations [Member]
Securities without maturity date, amortized cost	20,542
Securities without maturity date, fair value	20,859
Securities available-for-sale, amortized cost	20,542	33,001
Total securities available-for-sale	$ 20,859	$ 32,837

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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