Note 3 - Securities - Amortized Cost and Fair Value of Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Available-for-sale securities, Amortized cost	$ 185,269	$ 179,975
Available-for-sale securities, Gross unrealized gains	9,317	3,885
Available-for-sale securities, Gross unrealized losses	6	249
Available-for-sale securities, Fair Value	194,580	183,611
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, Amortized cost	93,406	70,043
Available-for-sale securities, Gross unrealized gains	6,400	2,593
Available-for-sale securities, Gross unrealized losses	1	82
Available-for-sale securities, Fair Value	99,805	72,554
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Available-for-sale securities, Amortized cost	90,712	108,907
Available-for-sale securities, Gross unrealized gains	2,904	1,292
Available-for-sale securities, Gross unrealized losses	5	158
Available-for-sale securities, Fair Value	93,611	110,041
Other Debt Obligations [Member]
Available-for-sale securities, Amortized cost	1,151	1,025
Available-for-sale securities, Gross unrealized gains	13
Available-for-sale securities, Gross unrealized losses		9
Available-for-sale securities, Fair Value	$ 1,164	$ 1,016

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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