Note 2 - Securities - Maturity of Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Due in one year or less, amortized cost	$ 497
Due in one year or less, fair value	500
Due after one year through five years, amortized cost	4,547
Due after one year through five years, fair value	4,631
Due after five through ten years, amortized cost	25,648
Due after five years through ten years, fair value	26,215
Due after ten years, amortized cost	47,731
Due after ten years, fair value	49,203
Securities available-for-sale, amortized cost	110,232	$ 120,245
Securities available-for-sale, fair value	113,041	120,107
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities without maturity date, amortized cost	16,151
Securities without maturity date, fair value	16,581
Securities available-for-sale, amortized cost	16,151	40,868
Securities available-for-sale, fair value	16,581	41,075
Collateralized Mortgage Obligations [Member]
Securities without maturity date, amortized cost	15,658
Securities without maturity date, fair value	15,911
Securities available-for-sale, amortized cost	15,658	33,001
Securities available-for-sale, fair value	$ 15,911	$ 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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