Note 2 - Securities - Available-for-sale Securities (Details) - USD ($)	Sep. 30, 2019	Dec. 31, 2018
Securities available for sale, amortized cost	$ 340,141,000	$ 347,795,000
Securities available for sale, gross unrealized gains	6,489,000	928,000
Securities available for sale, gross unrealized losses	(1,097,000)	(11,357,000)
Fair value	345,533,000	337,366,000
US Government Agencies Debt Securities [Member]
Securities available for sale, amortized cost	195,926,000	196,109,000
Securities available for sale, gross unrealized gains	3,151,000	310,000
Securities available for sale, gross unrealized losses	(958,000)	(9,342,000)
Fair value	198,119,000	187,077,000
Collateralized Mortgage Backed Securities [Member]
Securities available for sale, amortized cost	42,563,000	44,263,000
Securities available for sale, gross unrealized gains	524,000	187,000
Securities available for sale, gross unrealized losses	(116,000)	(792,000)
Fair value	42,971,000	43,658,000
Municipal General Obligation Bonds [Member]
Securities available for sale, amortized cost	97,806,000	103,235,000
Securities available for sale, gross unrealized gains	2,753,000	427,000
Securities available for sale, gross unrealized losses	(22,000)	(1,165,000)
Fair value	100,537,000	102,497,000
Municipal Revenue Bonds [Member]
Securities available for sale, amortized cost	3,346,000	3,688,000
Securities available for sale, gross unrealized gains	61,000	4,000
Securities available for sale, gross unrealized losses	(1,000)	(58,000)
Fair value	3,406,000	3,634,000
Other Debt and Equity Securities [Member]
Securities available for sale, amortized cost	500,000	500,000
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	0	0
Fair value	$ 500,000	$ 500,000

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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-SubTopic 10
-Section 50
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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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