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Note 18 - Fair Values Measurements (Details) - Assets and Liabilities Measured at Fair Value on a Recurring Basis - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Available for sale securities
Available for sale securities	$ 346,992,000	$ 432,912,000
Interest Rate Swap [Member] | Fair Value, Measurements, Recurring [Member]
Derivatives
Derivative	(253,000)	(253,000)
Assets and liabilities measured at fair value on recurring basis	346,739,000	432,659,000
US Government Agencies Debt Securities [Member]
Available for sale securities
Available for sale securities	147,040,000	193,468,000
US Government Agencies Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities	147,040,000	193,468,000
Collateralized Mortgage Backed Securities [Member]
Available for sale securities
Available for sale securities	67,074,000	93,561,000
Collateralized Mortgage Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities	67,074,000	93,561,000
Municipal General Obligation Bonds [Member]
Available for sale securities
Available for sale securities	122,023,000	133,082,000
Municipal General Obligation Bonds [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities	122,023,000	133,082,000
Municipal Revenue Bonds [Member]
Available for sale securities
Available for sale securities	8,914,000	10,873,000
Municipal Revenue Bonds [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities	8,914,000	10,873,000
Other Debt Obligations [Member]
Available for sale securities
Available for sale securities	1,941,000	1,928,000
Other Debt Obligations [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities	1,941,000
Mutual Funds [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities		1,928,000
Fair Value, Inputs, Level 1 [Member]
Available for sale securities
Available for sale securities	0
Fair Value, Inputs, Level 1 [Member] | Interest Rate Swap [Member] | Fair Value, Measurements, Recurring [Member]
Derivatives
Derivative	0	0
Assets and liabilities measured at fair value on recurring basis	0	0
Fair Value, Inputs, Level 1 [Member] | US Government Agencies Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities	0	0
Fair Value, Inputs, Level 1 [Member] | Collateralized Mortgage Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities	0	0
Fair Value, Inputs, Level 1 [Member] | Municipal General Obligation Bonds [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities	0	0
Fair Value, Inputs, Level 1 [Member] | Municipal Revenue Bonds [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities	0	0
Fair Value, Inputs, Level 1 [Member] | Other Debt Obligations [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities	0
Fair Value, Inputs, Level 1 [Member] | Mutual Funds [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities		0
Fair Value, Inputs, Level 2 [Member] | Interest Rate Swap [Member] | Fair Value, Measurements, Recurring [Member]
Derivatives
Derivative	(253,000)	(253,000)
Assets and liabilities measured at fair value on recurring basis	338,320,000	422,378,000
Fair Value, Inputs, Level 2 [Member] | US Government Agencies Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities	147,040,000	193,468,000
Fair Value, Inputs, Level 2 [Member] | Collateralized Mortgage Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities	67,074,000	93,561,000
Fair Value, Inputs, Level 2 [Member] | Municipal General Obligation Bonds [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities	113,604,000	122,801,000
Fair Value, Inputs, Level 2 [Member] | Municipal Revenue Bonds [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities	8,914,000	10,873,000
Fair Value, Inputs, Level 2 [Member] | Other Debt Obligations [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities	1,941,000
Fair Value, Inputs, Level 2 [Member] | Mutual Funds [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities		1,928,000
Fair Value, Inputs, Level 3 [Member] | Interest Rate Swap [Member] | Fair Value, Measurements, Recurring [Member]
Derivatives
Derivative	0	0
Assets and liabilities measured at fair value on recurring basis	8,419,000	10,281,000
Fair Value, Inputs, Level 3 [Member] | US Government Agencies Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities	0	0
Fair Value, Inputs, Level 3 [Member] | Collateralized Mortgage Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities	0	0
Fair Value, Inputs, Level 3 [Member] | Municipal General Obligation Bonds [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities	8,419,000	10,281,000
Fair Value, Inputs, Level 3 [Member] | Municipal Revenue Bonds [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities	0	0
Fair Value, Inputs, Level 3 [Member] | Other Debt Obligations [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities	$ 0
Fair Value, Inputs, Level 3 [Member] | Mutual Funds [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities		$ 0

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Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Name Accounting Standards Codification
-Topic 320
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-Section 45
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Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
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