Note 5 - Investment Securities (Details) - Investment Securities by Contractual Maturity (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Investment Securities by Contractual Maturity [Abstract]
Due in 1 year or less	$ 13,398
Due in 1 year or less	13,498
Due in 1 year or less	0
Due in 1 year or less	0
After 1 year to 5 years	86,809
After 1 year to 5 years	87,202
After 1 year to 5 years	43,315
After 1 year to 5 years	44,104
After 5 years to 10 years	75,048
After 5 years to 10 years	75,062
After 5 years to 10 years	23,427
After 5 years to 10 years	23,774
After 10 years	11,007
After 10 years	11,262
After 10 years	0
After 10 years	0
Total	186,262
Total	187,024us-gaap_AvailableForSaleSecurities	185,379us-gaap_AvailableForSaleSecurities
Total	66,742us-gaap_HeldToMaturitySecurities	67,866us-gaap_HeldToMaturitySecurities
Total	$ 67,878	$ 68,253

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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.