Note 3 - Securities (Details) - Available-for-sale Securities - USD ($)	Dec. 31, 2015	Dec. 31, 2014
2015
Available-for-sale Securities, Amortized Cost	$ 344,796,000	$ 432,591,000
Available-for-sale Securities, Gross Unrealized Gains	4,265,000	3,897,000
Available-for-sale Securities, Gross Unrealized Losses	(2,069,000)	(3,576,000)
Securities available for sale	346,992,000	432,912,000
US Government Agencies Debt Securities [Member]
2015
Available-for-sale Securities, Amortized Cost	146,660,000	194,894,000
Available-for-sale Securities, Gross Unrealized Gains	1,932,000	1,612,000
Available-for-sale Securities, Gross Unrealized Losses	(1,552,000)	(3,038,000)
Securities available for sale	147,040,000	193,468,000
Collateralized Mortgage Backed Securities [Member]
2015
Available-for-sale Securities, Amortized Cost	66,670,000	92,656,000
Available-for-sale Securities, Gross Unrealized Gains	708,000	1,123,000
Available-for-sale Securities, Gross Unrealized Losses	(304,000)	(218,000)
Securities available for sale	67,074,000	93,561,000
Municipal General Obligation Bonds [Member]
2015
Available-for-sale Securities, Amortized Cost	120,679,000	132,347,000
Available-for-sale Securities, Gross Unrealized Gains	1,549,000	1,042,000
Available-for-sale Securities, Gross Unrealized Losses	(205,000)	(307,000)
Securities available for sale	122,023,000	133,082,000
Municipal Revenue Bonds [Member]
2015
Available-for-sale Securities, Amortized Cost	8,841,000	10,769,000
Available-for-sale Securities, Gross Unrealized Gains	76,000	117,000
Available-for-sale Securities, Gross Unrealized Losses	(3,000)	(13,000)
Securities available for sale	8,914,000	10,873,000
Other Debt Obligations [Member]
2015
Available-for-sale Securities, Amortized Cost	1,946,000	1,925,000
Available-for-sale Securities, Gross Unrealized Gains	0	3,000
Available-for-sale Securities, Gross Unrealized Losses	(5,000)	0
Securities available for sale	$ 1,941,000	$ 1,928,000

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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-Publisher FASB
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-Topic 320
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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 2
-Subparagraph (c)
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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.2)
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