Note 2 - Securities - Amortized Cost, Gross Unrealized Gains or Losses, and Fair Value of Investment Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Available for sale securities, amortized cost	$ 201,455	$ 207,672
Available for sale securities, gross unrealized gains	3,326	2,145
Available for sale securities, gross unrealized losses	(6,124)	(817)
Securities available for sale	198,657	209,000
US Treasury and Government [Member]
Available for sale securities, amortized cost	20,751	22,281
Available for sale securities, gross unrealized gains	353	196
Available for sale securities, gross unrealized losses		(147)
Securities available for sale	21,104	22,330
Residential Mortgage Backed Securities [Member]
Available for sale securities, amortized cost	86,840	91,269
Available for sale securities, gross unrealized gains	2,428	1,186
Available for sale securities, gross unrealized losses	(167)	(255)
Securities available for sale	89,101	92,200
Collateralized Debt Obligations [Member]
Available for sale securities, amortized cost	44,732	49,831
Available for sale securities, gross unrealized gains
Available for sale securities, gross unrealized losses	(3,978)	(412)
Securities available for sale	40,754	49,419
US States and Political Subdivisions Debt Securities [Member]
Available for sale securities, amortized cost	28,301	27,819
Available for sale securities, gross unrealized gains	346	550
Available for sale securities, gross unrealized losses	(493)	(3)
Securities available for sale	28,154	28,366
Corporate Debt Securities [Member]
Available for sale securities, amortized cost	20,831	16,472
Available for sale securities, gross unrealized gains	199	213
Available for sale securities, gross unrealized losses	(1,486)
Securities available for sale	$ 19,544	$ 16,685

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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