Note 3 - Securities - Securities Reconciliation (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Available-for-sale securities:
Available-for-sale securities, amortized costs	$ 259,812	$ 268,406
Available-for-sale securities, gross unrealized gain	1,697	2,221
Available-for-sale securities, gross unrealized loss	(5,592)	(2,673)
Securities available-for-sale	255,917	267,954
US Government Agencies Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	41,261	40,319
Available-for-sale securities, gross unrealized gain	270	196
Available-for-sale securities, gross unrealized loss	(352)	(146)
Securities available-for-sale	41,179	40,369
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	58,832	77,412
Available-for-sale securities, gross unrealized gain	1,387	1,910
Available-for-sale securities, gross unrealized loss	(811)	(478)
Securities available-for-sale	59,408	78,844
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	129,111	116,061
Available-for-sale securities, gross unrealized gain	18	69
Available-for-sale securities, gross unrealized loss	(3,562)	(1,538)
Securities available-for-sale	125,567	114,592
Corporate Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	4,065	5,079
Available-for-sale securities, gross unrealized gain	7	18
Available-for-sale securities, gross unrealized loss	(114)	(105)
Securities available-for-sale	3,958	4,992
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	26,261	26,995
Available-for-sale securities, gross unrealized gain	12	24
Available-for-sale securities, gross unrealized loss	(753)	(378)
Securities available-for-sale	25,520	26,641
Asset-backed Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	282	2,540
Available-for-sale securities, gross unrealized gain	3	4
Available-for-sale securities, gross unrealized loss		(28)
Securities available-for-sale	$ 285	$ 2,516

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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-Section 50
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