Note 2 - Investment Securities - Available-for-sale Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Securities available-for-sale, amortized cost	$ 46,003	$ 55,523
Securities available-for-sale, gross unrealized gains	137	404
Securities available-for-sale, gross unrealized losses	(1,164)	(583)
Securities available for sale, at fair value	44,976	55,344
US Government Agencies Debt Securities [Member]
Securities available-for-sale, amortized cost	10,738	13,475
Securities available-for-sale, gross unrealized gains	33	61
Securities available-for-sale, gross unrealized losses	(189)	(101)
Securities available for sale, at fair value	10,582	13,435
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Securities available-for-sale, amortized cost	19,525	24,344
Securities available-for-sale, gross unrealized gains		12
Securities available-for-sale, gross unrealized losses	(596)	(375)
Securities available for sale, at fair value	18,929	23,981
Corporate Debt Securities [Member]
Securities available-for-sale, amortized cost	6,641	6,991
Securities available-for-sale, gross unrealized gains	37	118
Securities available-for-sale, gross unrealized losses	(239)	(42)
Securities available for sale, at fair value	6,439	7,067
US States and Political Subdivisions Debt Securities [Member]
Securities available-for-sale, amortized cost	9,099	10,713
Securities available-for-sale, gross unrealized gains	67	213
Securities available-for-sale, gross unrealized losses	(140)	(65)
Securities available for sale, at fair value	$ 9,026	$ 10,861

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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