Note 2 - Securities - Securities With Unrealized Losses (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Available for sale, fair value, less than 12 months	$ 41,474	$ 91,656
Available for sale, unrealized loss, less than 12 months	(293)	(558)
Available for sale, fair value, 12 months or more	46,001	65,396
Available for sale, unrealized loss, 12 months or more	(524)	(2,443)
Available for sale, fair value	87,475	157,052
Available for sale, unrealized loss	(817)	(3,001)
US Treasury and Government [Member]
Available for sale, fair value, less than 12 months	12,567	3,431
Available for sale, unrealized loss, less than 12 months	(147)	(57)
Available for sale, fair value, 12 months or more		17,212
Available for sale, unrealized loss, 12 months or more		(665)
Available for sale, fair value	12,567	20,643
Available for sale, unrealized loss	(147)	(722)
Residential Mortgage Backed Securities [Member]
Available for sale, fair value, less than 12 months	18,457	30,229
Available for sale, unrealized loss, less than 12 months	(97)	(343)
Available for sale, fair value, 12 months or more	10,665	40,932
Available for sale, unrealized loss, 12 months or more	(158)	(1,548)
Available for sale, fair value	29,122	71,161
Available for sale, unrealized loss	(255)	(1,891)
Collateralized Loan Obligations [Member]
Available for sale, fair value, less than 12 months	9,539	48,294
Available for sale, unrealized loss, less than 12 months	(46)	(103)
Available for sale, fair value, 12 months or more	35,336
Available for sale, unrealized loss, 12 months or more	(366)
Available for sale, fair value	44,875	48,294
Available for sale, unrealized loss	(412)	(103)
US States and Political Subdivisions Debt Securities [Member]
Available for sale, fair value, less than 12 months	911	6,133
Available for sale, unrealized loss, less than 12 months	(3)	(29)
Available for sale, fair value, 12 months or more		7,252
Available for sale, unrealized loss, 12 months or more		(230)
Available for sale, fair value	911	13,385
Available for sale, unrealized loss	(3)	(259)
Corporate Debt Securities [Member]
Available for sale, fair value, less than 12 months		3,569
Available for sale, unrealized loss, less than 12 months		(26)
Available for sale, fair value, 12 months or more
Available for sale, unrealized loss, 12 months or more
Available for sale, fair value		3,569
Available for sale, unrealized loss		$ (26)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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