Note 2 - Securities - Amortized Cost, Gross Unrealized Gains or Losses, and Fair Value of Investment Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Available for sale securities, amortized cost	$ 207,672	$ 203,642
Available for sale securities, gross unrealized gains	2,145	551
Available for sale securities, gross unrealized losses	(817)	(3,001)
Securities available for sale	209,000	201,192
US Treasury and Government [Member]
Available for sale securities, amortized cost	22,281	23,280
Available for sale securities, gross unrealized gains	196	2
Available for sale securities, gross unrealized losses	(147)	(722)
Securities available for sale	22,330	22,560
Residential Mortgage Backed Securities [Member]
Available for sale securities, amortized cost	91,269	87,689
Available for sale securities, gross unrealized gains	1,186	192
Available for sale securities, gross unrealized losses	(255)	(1,891)
Securities available for sale	92,200	85,990
Collateralized Debt Obligations [Member]
Available for sale securities, amortized cost	49,831	49,942
Available for sale securities, gross unrealized gains
Available for sale securities, gross unrealized losses	(412)	(103)
Securities available for sale	49,419	49,839
US States and Political Subdivisions Debt Securities [Member]
Available for sale securities, amortized cost	27,819	32,841
Available for sale securities, gross unrealized gains	550	230
Available for sale securities, gross unrealized losses	(3)	(259)
Securities available for sale	28,366	32,812
Corporate Debt Securities [Member]
Available for sale securities, amortized cost	16,472	9,890
Available for sale securities, gross unrealized gains	213	127
Available for sale securities, gross unrealized losses		(26)
Securities available for sale	$ 16,685	$ 9,991

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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