Note 4 - Securities - Amortized Cost and Fair Value of Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Available-for-sale securities, Amortized cost	$ 179,975	$ 169,587
Available-for-sale securities, Gross unrealized gains	3,885	516
Available-for-sale securities, Gross unrealized losses	249	2,749
Available-for-sale securities, Fair Value	183,611	167,354
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, Amortized cost	70,043	59,585
Available-for-sale securities, Gross unrealized gains	2,593	354
Available-for-sale securities, Gross unrealized losses	82	473
Available-for-sale securities, Fair Value	72,554	59,466
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Available-for-sale securities, Amortized cost	108,907	109,000
Available-for-sale securities, Gross unrealized gains	1,292	162
Available-for-sale securities, Gross unrealized losses	158	2,238
Available-for-sale securities, Fair Value	110,041	106,924
Other Debt Obligations [Member]
Available-for-sale securities, Amortized cost	1,025	1,002
Available-for-sale securities, Gross unrealized gains
Available-for-sale securities, Gross unrealized losses	9	38
Available-for-sale securities, Fair Value	$ 1,016	$ 964

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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