Note 2 - Securities - Summary of Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Debt securities, amortized cost	$ 120,245	$ 99,639
Debt securities, gross unrealized gains	686	86
Debt securities, gross unrealized gains	(824)	(2,007)
Debt securities, fair value	120,107	97,718
US Government-sponsored Enterprises Debt Securities [Member]
Debt securities, amortized cost	7,069	17,052
Debt securities, gross unrealized gains	14	30
Debt securities, gross unrealized gains	(6)	(299)
Debt securities, fair value	7,077	16,783
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Debt securities, amortized cost	40,868	27,666
Debt securities, gross unrealized gains	291
Debt securities, gross unrealized gains	(84)	(490)
Debt securities, fair value	41,075	27,176
Collateralized Mortgage Obligations [Member]
Debt securities, amortized cost	33,001	19,440
Debt securities, gross unrealized gains	71	34
Debt securities, gross unrealized gains	(235)	(810)
Debt securities, fair value	32,837	18,664
US States and Political Subdivisions Debt Securities [Member]
Debt securities, amortized cost	27,848	22,943
Debt securities, gross unrealized gains	217	13
Debt securities, gross unrealized gains	(269)	(224)
Debt securities, fair value	27,796	22,732
Corporate Debt Securities [Member]
Debt securities, amortized cost	11,459	8,006
Debt securities, gross unrealized gains	93	9
Debt securities, gross unrealized gains	(230)	(97)
Debt securities, fair value	$ 11,322	7,918
US Treasury and Government [Member]
Debt securities, amortized cost		4,532
Debt securities, gross unrealized gains
Debt securities, gross unrealized gains		(87)
Debt securities, fair value		$ 4,445

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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