Note 3 - Debt Securities - Securities Available-for-sale (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Securities available for sale, amortized cost	$ 81,958	$ 168,478
Securities available for sale, unrealized gains	1,501	1,266
Securities available for sale, unrealized losses	(101)	(170)
Securities available for sale, fair value	83,358	169,574
US Government Agencies Debt Securities [Member]
Securities available for sale, amortized cost	555	5,038
Securities available for sale, unrealized gains	0	0
Securities available for sale, unrealized losses	(4)	(4)
Securities available for sale, fair value	551	5,034
US States and Political Subdivisions Debt Securities [Member]
Securities available for sale, amortized cost	43,950	85,992
Securities available for sale, unrealized gains	509	886
Securities available for sale, unrealized losses	0	0
Securities available for sale, fair value	44,459	86,878
Mortgage-backed Agency Securities [Member]
Securities available for sale, amortized cost	37,453	77,448
Securities available for sale, unrealized gains	992	380
Securities available for sale, unrealized losses	(97)	(166)
Securities available for sale, fair value	$ 38,348	$ 77,662

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on 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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