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Note 11 - Fair Values (Details) - Assets and Liabilities Measured at Fair Value on a Recurring Basis - USD ($)		Sep. 30, 2015	Dec. 31, 2014
Available for sale securities
Available for sale securities	[1]	$ 367,173,000	$ 432,912,000
Interest Rate Swap [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Derivative		(533,000)	(253,000)
Assets and liabilities measured at fair value on recurring basis		366,640,000	432,659,000
US Government Agencies Debt Securities [Member]
Available for sale securities
Available for sale securities		159,393,000	193,468,000
US Government Agencies Debt Securities [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities		159,393,000	193,468,000
Collateralized Mortgage Backed Securities [Member]
Available for sale securities
Available for sale securities		72,964,000	93,561,000
Collateralized Mortgage Backed Securities [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities		72,964,000	93,561,000
Municipal General Obligation Bonds [Member]
Available for sale securities
Available for sale securities		123,608,000	133,082,000
Municipal General Obligation Bonds [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities		123,608,000	133,082,000
Municipal Revenue Bonds [Member]
Available for sale securities
Available for sale securities		9,250,000	10,873,000
Municipal Revenue Bonds [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities		9,250,000	10,873,000
Other Debt Obligations [Member]
Available for sale securities
Available for sale securities		1,958,000	1,928,000
Other Debt Obligations [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Available for sale securities		1,958,000	1,928,000
Fair Value, Inputs, Level 1 [Member] | Interest Rate Swap [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
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	0
Fair Value, Inputs, Level 2 [Member] | Interest Rate Swap [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Derivative		(533,000)	(253,000)
Assets and liabilities measured at fair value on recurring basis		358,151,000	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		159,393,000	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		72,964,000	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		115,119,000	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		9,250,000	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		1,958,000	1,928,000
Fair Value, Inputs, Level 3 [Member] | Interest Rate Swap [Member] | Fair Value, Measurements, Recurring [Member]
Available for sale securities
Derivative		0	0
Assets and liabilities measured at fair value on recurring basis		8,489,000	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		8,489,000	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	$ 0
[1] See Note 11 for a description of the fair value hierarchy as well as a disclosure of levels for classes of financial assets and liabilities.

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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.

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

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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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