Note 3 - Securities - Securities Reconciliation (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Available-for-sale securities:
Available-for-sale securities, amortized costs	$ 245,424	$ 268,407
Available-for-sale securities, gross unrealized gain	1,135	2,221
Available-for-sale securities, gross unrealized loss	(6,926)	(2,674)
Securities available-for-sale	239,633	267,954
US Government Agencies Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	36,057	40,319
Available-for-sale securities, gross unrealized gain	111	196
Available-for-sale securities, gross unrealized loss	(512)	(146)
Securities available-for-sale	35,656	40,369
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	51,468	77,412
Available-for-sale securities, gross unrealized gain	1,003	1,910
Available-for-sale securities, gross unrealized loss	(909)	(478)
Securities available-for-sale	51,562	78,844
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	128,703	116,062
Available-for-sale securities, gross unrealized gain	6	69
Available-for-sale securities, gross unrealized loss	(4,600)	(1,539)
Securities available-for-sale	124,109	114,592
Corporate Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	4,042	5,079
Available-for-sale securities, gross unrealized gain	5	18
Available-for-sale securities, gross unrealized loss	(73)	(105)
Securities available-for-sale	3,974	4,992
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	24,990	26,995
Available-for-sale securities, gross unrealized gain	9	24
Available-for-sale securities, gross unrealized loss	(832)	(378)
Securities available-for-sale	24,167	26,641
Asset-backed Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	164	2,540
Available-for-sale securities, gross unrealized gain	1	4
Available-for-sale securities, gross unrealized loss		(28)
Securities available-for-sale	$ 165	$ 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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