Note 3 - Securities - Securities Available-for-sale (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Securities available for sale, amortized cost	$ 110,987	$ 104,867
Securities available for sale, gross unrealized gains	480	100
Securities available for sale, gross unrealized losses	(1,186)	(2,803)
Securities available for sale	110,281	102,164
US Government-sponsored Enterprises Debt Securities [Member]
Securities available for sale, amortized cost	16,677	16,837
Securities available for sale, gross unrealized gains	91	8
Securities available for sale, gross unrealized losses	(79)	(215)
Securities available for sale	16,689	16,630
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available for sale, amortized cost	94,310	88,030
Securities available for sale, gross unrealized gains	389	92
Securities available for sale, gross unrealized losses	(1,107)	(2,588)
Securities available for sale	$ 93,592	$ 85,534

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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