Note 3 - Securities - Securities Reconciliation (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Available-for-sale securities:
Available-for-sale securities, amortized costs	$ 252,522	$ 268,406
Available-for-sale securities, gross unrealized gain	1,516	2,221
Available-for-sale securities, gross unrealized loss	(6,399)	(2,673)
Securities available-for-sale	247,639	267,954
US Government Agencies Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	39,377	40,319
Available-for-sale securities, gross unrealized gain	126	196
Available-for-sale securities, gross unrealized loss	(509)	(146)
Securities available-for-sale	38,994	40,369
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	57,867	77,412
Available-for-sale securities, gross unrealized gain	1,365	1,910
Available-for-sale securities, gross unrealized loss	(753)	(478)
Securities available-for-sale	58,479	78,844
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	125,466	116,061
Available-for-sale securities, gross unrealized gain	6	69
Available-for-sale securities, gross unrealized loss	(4,254)	(1,538)
Securities available-for-sale	121,218	114,592
Corporate Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	4,054	5,079
Available-for-sale securities, gross unrealized gain	6	18
Available-for-sale securities, gross unrealized loss	(73)	(105)
Securities available-for-sale	3,987	4,992
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	25,541	26,995
Available-for-sale securities, gross unrealized gain	11	24
Available-for-sale securities, gross unrealized loss	(810)	(378)
Securities available-for-sale	24,742	26,641
Asset-backed Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	217	2,540
Available-for-sale securities, gross unrealized gain	2	4
Available-for-sale securities, gross unrealized loss		(28)
Securities available-for-sale	$ 219	$ 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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