Note 5 - Securities (Details) - Fair Value and Associated Unrealized Losses on Investments (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Available-for-sale securities:
Available-for-sale securities, less than 12 months, fair value	$ 16,177	$ 31,006
Available-for-sale securities, less than 12 months, unrealized losses	(109)	(166)
Available-for-sale securities, 12 months or more, fair value	17,050	22,884
Available-for-sale securities, 12 months or more, unrealized losses	(351)	(476)
Available-for-sale securities, fair value	33,227	53,890
Available-for-sale securities, unrealized losses	(460)	(642)
Obligations of States and Political Subdivisions [Member]
Available-for-sale securities:
Available-for-sale securities, less than 12 months, fair value	2,152	3,952
Available-for-sale securities, less than 12 months, unrealized losses	(8)	(34)
Available-for-sale securities, 12 months or more, fair value		2,078
Available-for-sale securities, 12 months or more, unrealized losses		(20)
Available-for-sale securities, fair value	2,152	6,030
Available-for-sale securities, unrealized losses	(8)	(54)
Held-to-maturity securities:
Held-to-maturity securities, less than 12 months, fair value	5,801	1,556
Held-to-maturity securities, less than 12 months, unrealized losses	(62)	(14)
Held-to-maturity securities, 12 months or more, fair value	5,291	12,726
Held-to-maturity securities, 12 months or more, unrealized losses	(274)	(386)
Held-to-maturity securities, fair value	11,092	14,282
Held-to-maturity securities, unrealized losses	(336)	(400)
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities:
Available-for-sale securities, less than 12 months, fair value	6,233	10,193
Available-for-sale securities, less than 12 months, unrealized losses	(70)	(66)
Available-for-sale securities, 12 months or more, fair value	5,242	5,365
Available-for-sale securities, 12 months or more, unrealized losses	(97)	(103)
Available-for-sale securities, fair value	11,475	15,558
Available-for-sale securities, unrealized losses	(167)	(169)
Corporate Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities, less than 12 months, fair value	3,016	7,058
Available-for-sale securities, less than 12 months, unrealized losses	(15)	(36)
Available-for-sale securities, 12 months or more, fair value	3,777	6,542
Available-for-sale securities, 12 months or more, unrealized losses	(31)	(97)
Available-for-sale securities, fair value	6,793	13,600
Available-for-sale securities, unrealized losses	(46)	(133)
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities:
Available-for-sale securities, less than 12 months, fair value	2,106	4,912
Available-for-sale securities, less than 12 months, unrealized losses	(10)	(14)
Available-for-sale securities, 12 months or more, fair value	1,986	1,542
Available-for-sale securities, 12 months or more, unrealized losses	(46)	(59)
Available-for-sale securities, fair value	4,092	6,454
Available-for-sale securities, unrealized losses	(56)	(73)
Asset-backed Securities [Member]
Available-for-sale securities:
Available-for-sale securities, less than 12 months, fair value	2,670	4,891
Available-for-sale securities, less than 12 months, unrealized losses	(6)	(16)
Available-for-sale securities, 12 months or more, fair value	6,045	6,088
Available-for-sale securities, 12 months or more, unrealized losses	(177)	(181)
Available-for-sale securities, fair value	8,715	10,979
Available-for-sale securities, unrealized losses	(183)	(197)
US Government Agencies Debt Securities [Member]
Available-for-sale securities:
Available-for-sale securities, 12 months or more, fair value		1,269
Available-for-sale securities, 12 months or more, unrealized losses		(16)
Available-for-sale securities, fair value		1,269
Available-for-sale securities, unrealized losses		$ (16)

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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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