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Note 12 - Fair Values (Details) - Assets and Liabilities Measured at Fair Value on a Recurring Basis - USD ($) | Jun. 30, 2015 | Dec. 31, 2014
--- | --- | ---
Available for sale securities |  |  |
Available for sale securities | [1] | $ 373,446,000 | $ 432,912,000
Interest Rate Swap [Member] | Fair Value, Measurements, Recurring [Member] |  |  |
Available for sale securities |  |  |
Derivative |  | (379,000) | (253,000)
Assets and liabilities measured at fair value on recurring basis |  | 373,067,000 | 432,659,000
US Government Agencies Debt Securities [Member] |  |  |
Available for sale securities |  |  |
Available for sale securities |  | 161,708,000 | 193,468,000
US Government Agencies Debt Securities [Member] | Fair Value, Measurements, Recurring [Member] |  |  |
Available for sale securities |  |  |
Available for sale securities |  | 161,708,000 | 193,468,000
Collateralized Mortgage Backed Securities [Member] |  |  |
Available for sale securities |  |  |
Available for sale securities |  | 79,841,000 | 93,561,000
Collateralized Mortgage Backed Securities [Member] | Fair Value, Measurements, Recurring [Member] |  |  |
Available for sale securities |  |  |
Available for sale securities |  | 79,841,000 | 93,561,000
Municipal General Obligation Bonds [Member] |  |  |
Available for sale securities |  |  |
Available for sale securities |  | 119,811,000 | 133,082,000
Municipal General Obligation Bonds [Member] | Fair Value, Measurements, Recurring [Member] |  |  |
Available for sale securities |  |  |
Available for sale securities |  | 119,811,000 | 133,082,000
Municipal Revenue Bonds [Member] |  |  |
Available for sale securities |  |  |
Available for sale securities |  | 10,149,000 | 10,873,000
Municipal Revenue Bonds [Member] | Fair Value, Measurements, Recurring [Member] |  |  |
Available for sale securities |  |  |
Available for sale securities |  | 10,149,000 | 10,873,000
Other Debt Obligations [Member] |  |  |
Available for sale securities |  |  |
Available for sale securities |  | 1,937,000 | 1,928,000
Other Debt Obligations [Member] | Fair Value, Measurements, Recurring [Member] |  |  |
Available for sale securities |  |  |
Available for sale securities |  | 1,937,000 | 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 |  | (379,000) | (253,000)
Assets and liabilities measured at fair value on recurring basis |  | 364,278,000 | 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 |  | 161,708,000 | 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 |  | 79,841,000 | 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 |  | 111,022,000 | 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 |  | 10,149,000 | 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 |  | 1,937,000 | 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 |  | 8,789,000 | 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 |  | 8,789,000 | 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 12 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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