Note 3 - Investment Securities - Summary of Investment Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Securities available-for-sale, amortized cost	$ 125,072	$ 143,982
Securities available-for-sale, gross unrealized gains	2,288	408
Securities available-for-sale, gross unrealized losses	(485)	(2,225)
Securities available-for-sale	126,875	142,165
US Government Agencies Debt Securities [Member]
Securities available-for-sale, amortized cost	13,318	9,333
Securities available-for-sale, gross unrealized gains	279	58
Securities available-for-sale, gross unrealized losses		(44)
Securities available-for-sale	13,597	9,347
US States and Political Subdivisions Debt Securities [Member]
Securities available-for-sale, amortized cost	50,699	69,024
Securities available-for-sale, gross unrealized gains	1,616	244
Securities available-for-sale, gross unrealized losses	(93)	(990)
Securities available-for-sale	52,222	68,278
Corporate Debt Securities [Member]
Securities available-for-sale, amortized cost	8,356	11,411
Securities available-for-sale, gross unrealized gains	40	8
Securities available-for-sale, gross unrealized losses	(8)	(300)
Securities available-for-sale	8,388	11,119
Collateralized Mortgage Backed Securities [Member]
Securities available-for-sale, amortized cost	9,460	19,635
Securities available-for-sale, gross unrealized gains	56	86
Securities available-for-sale, gross unrealized losses	(21)	(373)
Securities available-for-sale	9,495	19,348
Collateralized Mortgage Obligations [Member]
Securities available-for-sale, amortized cost	33,129	24,229
Securities available-for-sale, gross unrealized gains	297	6
Securities available-for-sale, gross unrealized losses	(92)	(360)
Securities available-for-sale	33,334	23,875
Asset-backed Securities [Member]
Securities available-for-sale, amortized cost	10,110	10,350
Securities available-for-sale, gross unrealized gains		6
Securities available-for-sale, gross unrealized losses	(271)	(158)
Securities available-for-sale	$ 9,839	$ 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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