Note 3 - Securities - Securities Reconciliation (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Available-for-sale securities, amortized costs	$ 270,053	$ 283,257
Available-for-sale securities, gross unrealized gain	10,384	4,281
Available-for-sale securities, gross unrealized loss	(237)	(588)
Debt Securities, Available-for-sale	280,200	286,950
US Government Agencies Debt Securities [Member]
Available-for-sale securities, amortized costs	32,436	38,291
Available-for-sale securities, gross unrealized gain	775	469
Available-for-sale securities, gross unrealized loss	(16)	(27)
Debt Securities, Available-for-sale	33,195	38,733
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, amortized costs	72,958	40,702
Available-for-sale securities, gross unrealized gain	3,955	1,422
Available-for-sale securities, gross unrealized loss	(25)	(26)
Debt Securities, Available-for-sale	76,888	42,098
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities, amortized costs	132,226	179,114
Available-for-sale securities, gross unrealized gain	4,936	2,163
Available-for-sale securities, gross unrealized loss	(42)	(442)
Debt Securities, Available-for-sale	137,120	180,835
Corporate Debt Securities [Member]
Available-for-sale securities, amortized costs	1,000	3,005
Available-for-sale securities, gross unrealized gain	0	6
Available-for-sale securities, gross unrealized loss	0	(45)
Debt Securities, Available-for-sale	1,000	2,966
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities, amortized costs	15,715	19,126
Available-for-sale securities, gross unrealized gain	614	221
Available-for-sale securities, gross unrealized loss	0	(40)
Debt Securities, Available-for-sale	16,329	19,307
Asset-backed Securities [Member]
Available-for-sale securities, amortized costs	15,718	3,019
Available-for-sale securities, gross unrealized gain	104	0
Available-for-sale securities, gross unrealized loss	(154)	(8)
Debt Securities, Available-for-sale	$ 15,668	$ 3,011

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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