Note 2 - Securities - Summary of Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Debt securities, amortized cost	$ 110,232	$ 120,245
Debt securities, gross unrealized gains	2,925	686
Debt securities, gross unrealized losses	(116)	(824)
Debt securities, fair value	113,041	120,107
US Government-sponsored Enterprises Debt Securities [Member]
Debt securities, amortized cost	3,036	7,069
Debt securities, gross unrealized gains	11	14
Debt securities, gross unrealized losses	(40)	(6)
Debt securities, fair value	3,007	7,077
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Debt securities, amortized cost	16,151	40,868
Debt securities, gross unrealized gains	436	291
Debt securities, gross unrealized losses	(6)	(84)
Debt securities, fair value	16,581	41,075
Collateralized Mortgage Obligations [Member]
Debt securities, amortized cost	15,658	33,001
Debt securities, gross unrealized gains	263	71
Debt securities, gross unrealized losses	(10)	(235)
Debt securities, fair value	15,911	32,837
US States and Political Subdivisions Debt Securities [Member]
Debt securities, amortized cost	53,834	27,848
Debt securities, gross unrealized gains	1,781	217
Debt securities, gross unrealized losses	(38)	(269)
Debt securities, fair value	55,577	27,796
Corporate Debt Securities [Member]
Debt securities, amortized cost	21,553	11,459
Debt securities, gross unrealized gains	434	93
Debt securities, gross unrealized losses	(22)	(230)
Debt securities, fair value	$ 21,965	$ 11,322

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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