Note 3 - Securities - Securities Reconciliation (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Available-for-sale securities:
Available-for-sale securities, amortized costs	$ 294,818	$ 261,198
Available-for-sale securities, gross unrealized gain	2,444	1,431
Available-for-sale securities, gross unrealized loss	(3,145)	(5,701)
Securities available-for-sale	294,117	256,928
US Government Agencies Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	46,264	40,215
Available-for-sale securities, gross unrealized gain	316	202
Available-for-sale securities, gross unrealized loss	(129)	(330)
Securities available-for-sale	46,451	40,087
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	48,066	50,037
Available-for-sale securities, gross unrealized gain	1,146	1,082
Available-for-sale securities, gross unrealized loss	(277)	(589)
Securities available-for-sale	48,935	50,530
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	173,098	142,355
Available-for-sale securities, gross unrealized gain	950	129
Available-for-sale securities, gross unrealized loss	(2,234)	(3,981)
Securities available-for-sale	171,814	138,503
Corporate Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	3,018	3,022
Available-for-sale securities, gross unrealized gain
Available-for-sale securities, gross unrealized loss	(60)	(100)
Securities available-for-sale	2,958	2,922
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	24,277	25,446
Available-for-sale securities, gross unrealized gain	32	17
Available-for-sale securities, gross unrealized loss	(445)	(701)
Securities available-for-sale	23,864	24,762
Asset-backed Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	95	123
Available-for-sale securities, gross unrealized gain		1
Available-for-sale securities, gross unrealized loss
Securities available-for-sale	$ 95	$ 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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