Note 5 - Securities (Details) - Securities Available-for-sale (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Available for Sale:
Securities available-for-sale, amortized costs	$ 237,157	$ 225,279
Securities available-for-sale, gross unrealized gains	2,824	2,148
Securities available-for-sale, gross unrealized losses	1,485	4,583
Securities available-for-sale, fair value	238,496us-gaap_AvailableForSaleSecurities	222,844us-gaap_AvailableForSaleSecurities
US Government Agencies Debt Securities [Member]
Available for Sale:
Securities available-for-sale, amortized costs	210,729	197,740
Securities available-for-sale, gross unrealized gains	1,445	973
Securities available-for-sale, gross unrealized losses	1,417	4,494
Securities available-for-sale, fair value	210,757	194,219
US States and Political Subdivisions Debt Securities [Member]
Available for Sale:
Securities available-for-sale, amortized costs	17,583	18,529
Securities available-for-sale, gross unrealized gains	818	851
Securities available-for-sale, fair value	18,401	19,380
Collateralized Mortgage Backed Securities [Member]
Available for Sale:
Securities available-for-sale, amortized costs	1,665	1,830
Securities available-for-sale, gross unrealized gains	179	184
Securities available-for-sale, fair value	1,844	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	382	140
Securities available-for-sale, gross unrealized losses		27
Securities available-for-sale, fair value	7,373	7,104
Other Securities [Member]
Available for Sale:
Securities available-for-sale, amortized costs	189	189
Securities available-for-sale, gross unrealized losses	68	62
Securities available-for-sale, fair value	$ 121	$ 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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

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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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-Publisher FASB

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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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

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