Note 6 - Securities - Securities Available-for-sale (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Amortized cost	$ 274,886	$ 313,907
Gross unrealized gains	3,987	708
Gross unrealized losses	680	5,099
Fair value	278,193	309,516
US Government Agencies Debt Securities [Member]
Amortized cost	15,654	17,529
Gross unrealized gains	303	54
Gross unrealized losses	20	144
Fair value	15,937	17,439
Corporate Debt Securities [Member]
Amortized cost	23,774	13,052
Gross unrealized gains	98	76
Gross unrealized losses	158	436
Fair value	23,714	12,692
Collateralized Mortgage Backed Securities [Member]
Amortized cost	137,817	168,854
Gross unrealized gains	2,139	328
Gross unrealized losses	497	3,564
Fair value	139,459	165,618
US States and Political Subdivisions Debt Securities [Member]
Amortized cost	97,641	114,472
Gross unrealized gains	1,447	250
Gross unrealized losses	5	955
Fair value	$ 99,083	$ 113,767

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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