Note 3 - Securities - Securities Available-for-sale (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Securities available for sale, amortized cost	$ 110,745	$ 104,867
Securities available for sale, gross unrealized gains	872	100
Securities available for sale, gross unrealized losses	(375)	(2,803)
Securities available for sale	111,242	102,164
US Government-sponsored Enterprises Debt Securities [Member]
Securities available for sale, amortized cost	16,577	16,837
Securities available for sale, gross unrealized gains	171	8
Securities available for sale, gross unrealized losses	(12)	(215)
Securities available for sale	16,736	16,630
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available for sale, amortized cost	94,168	88,030
Securities available for sale, gross unrealized gains	701	92
Securities available for sale, gross unrealized losses	(363)	(2,588)
Securities available for sale	$ 94,506	$ 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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