Note 3 - Securities - Securities Reconciliation (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Available-for-sale securities:
Available-for-sale securities, amortized costs	$ 282,408	$ 261,198
Available-for-sale securities, gross unrealized gain	4,293	1,431
Available-for-sale securities, gross unrealized loss	(882)	(5,701)
Securities available-for-sale	285,819	256,928
US Government Agencies Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	44,334	40,215
Available-for-sale securities, gross unrealized gain	531	202
Available-for-sale securities, gross unrealized loss	(28)	(330)
Securities available-for-sale	44,837	40,087
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	43,585	50,037
Available-for-sale securities, gross unrealized gain	1,434	1,082
Available-for-sale securities, gross unrealized loss	(16)	(589)
Securities available-for-sale	45,003	50,530
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	166,683	142,355
Available-for-sale securities, gross unrealized gain	2,068	129
Available-for-sale securities, gross unrealized loss	(666)	(3,981)
Securities available-for-sale	168,085	138,503
Corporate Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	3,014	3,022
Available-for-sale securities, gross unrealized gain
Available-for-sale securities, gross unrealized loss	(36)	(100)
Securities available-for-sale	2,978	2,922
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	24,744	25,446
Available-for-sale securities, gross unrealized gain	260	17
Available-for-sale securities, gross unrealized loss	(136)	(701)
Securities available-for-sale	24,868	24,762
Asset-backed Securities [Member]
Available-for-sale securities:
Available-for-sale securities, amortized costs	48	123
Available-for-sale securities, gross unrealized gain		1
Available-for-sale securities, gross unrealized loss
Securities available-for-sale	$ 48	$ 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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