Note 4 - Securities (Details) - Fair Value and Associated Unrealized Losses on Investments (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Available-for-sale securities
Available-for-sale securities, less than 12 months, fair value	$ 31,006	$ 133,081
Available-for-sale securities, less than 12 months, unrealized losses	(166)	(4,454)
Available-for-sale securities, 12 months or more, fair value	22,884	12,937
Available-for-sale securities, 12 months or more, unrealized losses	(476)	(947)
Available-for-sale securities, fair value	53,890	146,018
Available-for-sale securities, unrealized losses	(642)	(5,401)
US Government Agencies Debt Securities [Member]
Available-for-sale securities
Available-for-sale securities, less than 12 months, fair value		5,446
Available-for-sale securities, less than 12 months, unrealized losses		(147)
Available-for-sale securities, 12 months or more, fair value	1,269	819
Available-for-sale securities, 12 months or more, unrealized losses	(16)	(168)
Available-for-sale securities, fair value	1,269	6,265
Available-for-sale securities, unrealized losses	(16)	(316)
Obligations of States and Political Subdivisions [Member]
Available-for-sale securities
Available-for-sale securities, less than 12 months, fair value	3,952	29,943
Available-for-sale securities, less than 12 months, unrealized losses	(34)	(1,578)
Available-for-sale securities, 12 months or more, fair value	2,078	2,727
Available-for-sale securities, 12 months or more, unrealized losses	(20)	(255)
Available-for-sale securities, fair value	6,030	32,670
Available-for-sale securities, unrealized losses	(54)	(1,833)
Held-to-maturity securities
Held-to-maturity securities, less than 12 months, fair value	1,556	23,800
Held-to-maturity securities, less than 12 months, unrealized losses	(14)	(1,524)
Held-to-maturity securities, 12 months or more, fair value	12,726	7,533
Held-to-maturity securities, 12 months or more, unrealized losses	(386)	(1,183)
Held-to-maturity securities, fair value	14,282	31,333
Held-to-maturity securities, unrealized losses	(400)	(2,707)
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities
Available-for-sale securities, less than 12 months, fair value	10,193	44,197
Available-for-sale securities, less than 12 months, unrealized losses	(66)	(1,214)
Available-for-sale securities, 12 months or more, fair value	5,365	3,271
Available-for-sale securities, 12 months or more, unrealized losses	(103)	(139)
Available-for-sale securities, fair value	15,558	47,468
Available-for-sale securities, unrealized losses	(169)	(1,353)
Corporate Debt Securities [Member]
Available-for-sale securities
Available-for-sale securities, less than 12 months, fair value	7,058	32,649
Available-for-sale securities, less than 12 months, unrealized losses	(36)	(792)
Available-for-sale securities, 12 months or more, fair value	6,542	2,960
Available-for-sale securities, 12 months or more, unrealized losses	(97)	(96)
Available-for-sale securities, fair value	13,600	35,609
Available-for-sale securities, unrealized losses	(133)	(888)
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities
Available-for-sale securities, less than 12 months, fair value	4,912	5,543
Available-for-sale securities, less than 12 months, unrealized losses	(14)	(205)
Available-for-sale securities, 12 months or more, fair value	1,542	1,437
Available-for-sale securities, 12 months or more, unrealized losses	(59)	(176)
Available-for-sale securities, fair value	6,454	6,980
Available-for-sale securities, unrealized losses	(73)	(380)
Asset-backed Securities [Member]
Available-for-sale securities
Available-for-sale securities, less than 12 months, fair value	4,891	15,303
Available-for-sale securities, less than 12 months, unrealized losses	(16)	(518)
Available-for-sale securities, 12 months or more, fair value	6,088	1,723
Available-for-sale securities, 12 months or more, unrealized losses	(181)	(113)
Available-for-sale securities, fair value	10,979	17,026
Available-for-sale securities, unrealized losses	$ (197)	$ (631)

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Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

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