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Note 2 - Securities - Available-for-sale Securities (Details) - USD ($)	Mar. 31, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale, Amortized Cost, Total	$ 350,335,000	$ 341,948,000
Gross Unrealized Gains	692,000	1,355,000
Gross Unrealized Losses	(14,039,000)	(7,559,000)
Fair Value	336,988,000	335,744,000
US Government Agencies Debt Securities [Member]
Debt Securities, Available-for-sale, Amortized Cost, Total	184,422,000	175,953,000
Gross Unrealized Gains	4,000	99,000
Gross Unrealized Losses	(11,257,000)	(6,352,000)
Fair Value	173,169,000	169,700,000
Collateralized Mortgage Backed Securities [Member]
Debt Securities, Available-for-sale, Amortized Cost, Total	41,104,000	38,967,000
Gross Unrealized Gains	278,000	335,000
Gross Unrealized Losses	(1,031,000)	(510,000)
Fair Value	40,351,000	38,792,000
Municipal General Obligation Bonds [Member]
Debt Securities, Available-for-sale, Amortized Cost, Total	118,881,000	121,040,000
Gross Unrealized Gains	404,000	891,000
Gross Unrealized Losses	(1,625,000)	(638,000)
Fair Value	117,660,000	121,293,000
Municipal Revenue Bonds [Member]
Debt Securities, Available-for-sale, Amortized Cost, Total	3,910,000	3,978,000
Gross Unrealized Gains	6,000	30,000
Gross Unrealized Losses	(73,000)	(30,000)
Fair Value	3,843,000	3,978,000
Other Debt and Equity Securities [Member]
Debt Securities, Available-for-sale, Amortized Cost, Total	2,018,000	2,010,000
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(53,000)	(29,000)
Fair Value	$ 1,965,000	$ 1,981,000

X

- Definition

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).

+ References

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-Section 50
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+ References

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+ References

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-Publisher FASB
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