Note 3 - Securities - Securities Reconciliation (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Available-for-sale securities:
Available-for-sale securities, amortized costs	$ 269,023	$ 261,198
Available-for-sale securities, gross unrealized gain	4,318	1,431
Available-for-sale securities, gross unrealized loss	(1,000)	(5,701)
Securities available-for-sale	272,341	256,928
US Government Agencies Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	39,955	40,215
Available-for-sale securities, gross unrealized gain	530	202
Available-for-sale securities, gross unrealized loss	(18)	(330)
Securities available-for-sale	40,467	40,087
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	37,401	50,037
Available-for-sale securities, gross unrealized gain	1,627	1,082
Available-for-sale securities, gross unrealized loss	(24)	(589)
Securities available-for-sale	39,004	50,530
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	164,975	142,355
Available-for-sale securities, gross unrealized gain	1,883	129
Available-for-sale securities, gross unrealized loss	(864)	(3,981)
Securities available-for-sale	165,994	138,503
Corporate Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	3,010	3,022
Available-for-sale securities, gross unrealized gain	4
Available-for-sale securities, gross unrealized loss	(22)	(100)
Securities available-for-sale	2,992	2,922
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	22,621	25,446
Available-for-sale securities, gross unrealized gain	273	17
Available-for-sale securities, gross unrealized loss	(72)	(701)
Securities available-for-sale	22,822	24,762
Asset-backed Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	1,061	123
Available-for-sale securities, gross unrealized gain	1	1
Available-for-sale securities, gross unrealized loss
Securities available-for-sale	$ 1,062	$ 124

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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