Note 3 - Debt Securities - Securities Available-for-sale (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Securities available for sale, amortized cost	$ 168,478	$ 153,477
Securities available for sale, unrealized gains	1,266	931
Securities available for sale, unrealized losses	(170)	(1,292)
Securities available for sale, fair value	169,574	153,116
US Government Agencies Debt Securities [Member]
Securities available for sale, amortized cost	5,038	1,108
Securities available for sale, unrealized gains		5
Securities available for sale, unrealized losses	(4)
Securities available for sale, fair value	5,034	1,113
US States and Political Subdivisions Debt Securities [Member]
Securities available for sale, amortized cost	85,992	96,886
Securities available for sale, unrealized gains	886	912
Securities available for sale, unrealized losses		(509)
Securities available for sale, fair value	86,878	97,289
US Treasury Securities [Member]
Securities available for sale, amortized cost		19,970
Securities available for sale, unrealized gains
Securities available for sale, unrealized losses		(10)
Securities available for sale, fair value		19,960
Mortgage-backed Agency Securities [Member]
Securities available for sale, amortized cost	77,448	35,513
Securities available for sale, unrealized gains	380	14
Securities available for sale, unrealized losses	(166)	(773)
Securities available for sale, fair value	$ 77,662	34,754
Single Issue Trust Preferred Securities [Member]
Securities available for sale, amortized cost
Securities available for sale, unrealized gains
Securities available for sale, unrealized losses
Securities available for sale, fair value

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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