Note 3 - Securities - Summary of Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt securities, amortized cost	$ 141,695	$ 110,232
Debt securities, gross unrealized gains	1,573	2,925
Debt securities, gross unrealized losses	(1,397)	(116)
Debt securities, fair value	141,871	113,041
US Government-sponsored Enterprises Debt Securities [Member]
Debt securities, amortized cost	6,035	3,036
Debt securities, gross unrealized gains	36	11
Debt securities, gross unrealized losses	(12)	(40)
Debt securities, fair value	6,059	3,007
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Debt securities, amortized cost	19,826	16,151
Debt securities, gross unrealized gains	340	436
Debt securities, gross unrealized losses	(121)	(6)
Debt securities, fair value	20,045	16,581
Collateralized Mortgage Obligations [Member]
Debt securities, amortized cost	22,573	15,658
Debt securities, gross unrealized gains	233	263
Debt securities, gross unrealized losses	(130)	(10)
Debt securities, fair value	22,676	15,911
US States and Political Subdivisions Debt Securities [Member]
Debt securities, amortized cost	69,519	53,834
Debt securities, gross unrealized gains	742	1,781
Debt securities, gross unrealized losses	(1,018)	(38)
Debt securities, fair value	69,243	55,577
Corporate Debt Securities [Member]
Debt securities, amortized cost	23,742	21,553
Debt securities, gross unrealized gains	222	434
Debt securities, gross unrealized losses	(116)	(22)
Debt securities, fair value	$ 23,848	$ 21,965

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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Amount, before tax, of unrealized loss 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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