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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	Sep. 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	$ 142,243	$ 150,476
Gross unrealized gains	3,971	5,095
Gross unrealized losses	(1,068)	(1,237)
Investment securities available for sale, at fair value	145,146	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	21,984	23,035
Gross unrealized gains	298	311
Gross unrealized losses	(264)	(450)
Investment securities available for sale, at fair value	22,018	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	1,990	2,953
Gross unrealized gains	156	226
Investment securities available for sale, at fair value	2,146	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	89,932	91,916
Gross unrealized gains	2,759	3,803
Gross unrealized losses	(664)	(553)
Investment securities available for sale, at fair value	92,027	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	25,400	29,150
Gross unrealized gains	409	475
Gross unrealized losses	(140)	(234)
Investment securities available for sale, at fair value	25,669	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	2,187	2,672
Gross unrealized gains	200	247
Investment securities available for sale, at fair value	2,387	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	141,493	149,726
Gross unrealized gains	3,822	5,062
Gross unrealized losses	(1,068)	(1,237)
Investment securities available for sale, at fair value	144,247	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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