Note 3 - Securities (Details) - Securities by Contractual Maturity (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Securities by Contractual Maturity [Abstract]
Due in one year or less	$ 1,864
Due in one year or less	1,899
Due after one year through five years	30,930
Due after one year through five years	31,171
Due after five years through ten years	30,161
Due after five years through ten years	30,156
Due after ten years	162,135
Due after ten years	159,491
No maturity	189
No maturity	127
	225,279
	222,844us-gaap_AvailableForSaleSecurities	181,712us-gaap_AvailableForSaleSecurities
Due in one year or less	1,637
Due in one year or less	1,650
Due after one year through five years	4,987
Due after one year through five years	5,262
Due after five years through ten years	24,052
Due after five years through ten years	25,181
Due after ten years	130,776
Due after ten years	135,610
	161,452us-gaap_HeldToMaturitySecurities	163,983us-gaap_HeldToMaturitySecurities
	$ 167,703	$ 159,337

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This item represents the cost of debt 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.