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Note 6 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Note 6 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items]
Amortized Cost	$ 155,903	$ 150,476
Gross Unrealized Gains	3,774	5,095
Gross Unrealized Losses	(2,100)	(1,237)
Investment securities available for sale, at fair value	157,577	154,334
US Government Agencies Debt Securities [Member]
Note 6 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items]
Amortized Cost	22,404	23,035
Gross Unrealized Gains	275	311
Gross Unrealized Losses	(457)	(450)
Investment securities available for sale, at fair value	22,222	22,896
US States and Political Subdivisions Debt Securities [Member] | Taxable [Member]
Note 6 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items]
Amortized Cost	1,991	2,953
Gross Unrealized Gains	129	226
Investment securities available for sale, at fair value	2,120	3,179
US States and Political Subdivisions Debt Securities [Member] | Tax-exempt [Member]
Note 6 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items]
Amortized Cost	101,595	91,916
Gross Unrealized Gains	2,652	3,803
Gross Unrealized Losses	(1,308)	(553)
Investment securities available for sale, at fair value	102,939	95,166
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Note 6 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items]
Amortized Cost	26,663	29,150
Gross Unrealized Gains	354	475
Gross Unrealized Losses	(335)	(234)
Investment securities available for sale, at fair value	26,682	29,391
Mortgage-backed Securities, Issued by Private Enterprises [Member]
Note 6 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items]
Amortized Cost	2,500	2,672
Gross Unrealized Gains	215	247
Investment securities available for sale, at fair value	2,715	2,919
Debt Securities [Member]
Note 6 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items]
Amortized Cost	155,153	149,726
Gross Unrealized Gains	3,625	5,062
Gross Unrealized Losses	(2,100)	(1,237)
Investment securities available for sale, at fair value	156,678	153,551
Equity Securities in Financial Institutions [Member]
Note 6 - Investment Securities Available for Sale (Details) - Amortized Cost and Fair Values of Securities Available for Sale [Line Items]
Amortized Cost	750	750
Gross Unrealized Gains	149	33
Investment securities available for sale, at fair value	$ 899	$ 783

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

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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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