Note 4 - Investment Securities - Amortized Cost and Fair Value of Investment Securities Classified as AFS (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Amortized Cost	$ 274,312	$ 263,913
Gross Unrealized Gains	2,433	4,916
Gross Unrealized Losses	(2,358)	(419)
Investment securities	274,387	268,410
US Government Corporations and Agencies Securities [Member]
Amortized Cost	23,064	36,648
Gross Unrealized Gains	172	201
Gross Unrealized Losses	(31)	(28)
Investment securities	23,205	36,821
US States and Political Subdivisions Debt Securities [Member]
Amortized Cost	26,503	21,650
Gross Unrealized Gains	499	490
Gross Unrealized Losses	(96)	(3)
Investment securities	26,906	22,137
Corporate Debt Securities [Member]
Amortized Cost	27,778	27,583
Gross Unrealized Gains	268	348
Gross Unrealized Losses	(222)	(223)
Investment securities	27,824	27,708
Residential Mortgage Backed Securities [Member]
Amortized Cost	127,227	119,934
Gross Unrealized Gains	1,080	2,675
Gross Unrealized Losses	(999)	(11)
Investment securities	127,308	122,598
Commercial Mortgage Backed Securities [Member]
Amortized Cost	69,740	58,098
Gross Unrealized Gains	414	1,202
Gross Unrealized Losses	(1,010)	(154)
Investment securities	$ 69,144	$ 59,146

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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