Note 3 - Securities - Maturity of Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Due in one year or less, amortized cost	$ 1,240
Due in one year or less, fair value	1,203
Due after one year through five years, amortized cost	2,067
Due after one year through five years, fair value	2,106
Due after five through ten years, amortized cost	14,994
Due after five through ten years, fair value	14,900
Due after ten years, amortized cost	23,255
Due after ten years, fair value	23,380
Debt securities, amortized cost	113,040	$ 120,245
Debt securities, fair value	114,419	120,107
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities without maturity date, amortized cost	40,099
Securities without maturity date, fair value	41,057
Debt securities, amortized cost	40,099	40,868
Debt securities, fair value	41,057	41,075
Collateralized Mortgage Obligations [Member]
Securities without maturity date, amortized cost	31,385
Securities without maturity date, fair value	31,773
Debt securities, amortized cost	31,385	33,001
Debt securities, fair value	$ 31,773	$ 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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