Note 3 - Investment Securities - Summary of Investment Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Securities available-for-sale, amortized cost	$ 133,632	$ 143,982
Securities available-for-sale, gross unrealized gains	3,097	408
Securities available-for-sale, gross unrealized losses	(346)	(2,225)
Securities available-for-sale, at fair value	136,383	142,165
US Government Agencies Debt Securities [Member]
Securities available-for-sale, amortized cost	13,817	9,333
Securities available-for-sale, gross unrealized gains	312	58
Securities available-for-sale, gross unrealized losses		(44)
Securities available-for-sale, at fair value	14,129	9,347
US States and Political Subdivisions Debt Securities [Member]
Securities available-for-sale, amortized cost	51,253	69,024
Securities available-for-sale, gross unrealized gains	2,103	244
Securities available-for-sale, gross unrealized losses	(1)	(990)
Securities available-for-sale, at fair value	53,355	68,278
Corporate Debt Securities [Member]
Securities available-for-sale, amortized cost	11,385	11,411
Securities available-for-sale, gross unrealized gains	43	8
Securities available-for-sale, gross unrealized losses	(25)	(300)
Securities available-for-sale, at fair value	11,403	11,119
Collateralized Mortgage Backed Securities [Member]
Securities available-for-sale, amortized cost	11,670	19,635
Securities available-for-sale, gross unrealized gains	67	86
Securities available-for-sale, gross unrealized losses	(50)	(373)
Securities available-for-sale, at fair value	11,687	19,348
Collateralized Mortgage Obligations [Member]
Securities available-for-sale, amortized cost	35,340	24,229
Securities available-for-sale, gross unrealized gains	572	6
Securities available-for-sale, gross unrealized losses	(89)	(360)
Securities available-for-sale, at fair value	35,823	23,875
Asset-backed Securities [Member]
Securities available-for-sale, amortized cost	10,167	10,350
Securities available-for-sale, gross unrealized gains		6
Securities available-for-sale, gross unrealized losses	(181)	(158)
Securities available-for-sale, at fair value	$ 9,986	$ 10,198

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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