Note 5 - Securities (Details) - Securities Available-for-sale - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Available for Sale:
Securities available-for-sale, amortized costs	$ 225,903	$ 225,279
Securities available-for-sale, gross unrealized gains	1,291	2,148
Securities available-for-sale, gross unrealized losses	8,670	4,583
Securities available-for-sale, fair value	218,524	222,844
US Government Agencies Debt Securities [Member]
Available for Sale:
Securities available-for-sale, amortized costs	200,713	197,740
Securities available-for-sale, gross unrealized gains	464	973
Securities available-for-sale, gross unrealized losses	8,231	4,494
Securities available-for-sale, fair value	192,946	194,219
US States and Political Subdivisions Debt Securities [Member]
Available for Sale:
Securities available-for-sale, amortized costs	16,481	18,529
Securities available-for-sale, gross unrealized gains	649	851
Securities available-for-sale, fair value	17,130	19,380
Collateralized Mortgage Backed Securities [Member]
Available for Sale:
Securities available-for-sale, amortized costs	1,530	1,830
Securities available-for-sale, gross unrealized gains	160	184
Securities available-for-sale, fair value	1,690	2,014
Corporate Debt Securities [Member]
Available for Sale:
Securities available-for-sale, amortized costs	6,991	6,991
Securities available-for-sale, gross unrealized gains	18	140
Securities available-for-sale, gross unrealized losses	386	27
Securities available-for-sale, fair value	6,623	7,104
Other Securities [Member]
Available for Sale:
Securities available-for-sale, amortized costs	188	189
Securities available-for-sale, gross unrealized losses	53	62
Securities available-for-sale, fair value	$ 135	$ 127

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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 gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

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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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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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