Note 3 - Securities - Securities Available-for-sale (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Securities available for sale, amortized cost	$ 103,469	$ 102,455
Securities available for sale, gross unrealized gains	106	300
Securities available for sale, gross unrealized losses	(3,410)	(1,630)
Securities available for sale	100,165	101,125
US Government-sponsored Enterprises Debt Securities [Member]
Securities available for sale, amortized cost	14,888	13,622
Securities available for sale, gross unrealized gains	6
Securities available for sale, gross unrealized losses	(306)	(149)
Securities available for sale	14,588	13,473
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available for sale, amortized cost	88,581	88,833
Securities available for sale, gross unrealized gains	100	300
Securities available for sale, gross unrealized losses	(3,104)	(1,481)
Securities available for sale	$ 85,577	$ 87,652

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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Amount, before tax, of unrealized loss 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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