Note 4 - Securities - Fair Value and Associated Unrealized Losses on Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
US States and Political Subdivisions Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value	$ 4,793	$ 7,682
Available-for-sale securities, less than 12 months, unrealized losses	(44)	(39)
Available-for-sale securities, fair value	4,793	7,682
Available-for-sale securities, unrealized losses	(44)	(39)
Held-to-maturity securities, less than 12 months, fair value	1,433	1,513
Held-to-maturity securities, less than 12 months, unrealized losses	(4)	(63)
Held-to-maturity securities, 12 months or more, fair value	1,023	4,831
Held-to-maturity securities, 12 months or more, unrealized losses	(7)	(157)
Held-to-maturity securities, fair value	2,456	6,344
Held-to-maturity securities, unrealized losses	(11)	(220)
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available-for-sale securities, less than 12 months, fair value	18,276	16,279
Available-for-sale securities, less than 12 months, unrealized losses	(109)	(210)
Available-for-sale securities, fair value	23,559	21,210
Available-for-sale securities, unrealized losses	(230)	(270)
Available-for-sale securities, 12 months or more, fair value	5,283	4,931
Available-for-sale securities, 12 months or more, unrealized losses	(121)	(60)
Corporate Debt Securities [Member]
Available-for-sale securities, less than 12 months, fair value	5,014	18,707
Available-for-sale securities, less than 12 months, unrealized losses	(55)	(191)
Available-for-sale securities, fair value	7,662	18,707
Available-for-sale securities, unrealized losses	(82)	(191)
Available-for-sale securities, 12 months or more, fair value	2,648
Available-for-sale securities, 12 months or more, unrealized losses	(27)
Commercial Mortgage Backed Securities [Member]
Available-for-sale securities, less than 12 months, fair value	8,155	7,557
Available-for-sale securities, less than 12 months, unrealized losses	(43)	(62)
Available-for-sale securities, fair value	11,099	9,073
Available-for-sale securities, unrealized losses	(61)	(134)
Available-for-sale securities, 12 months or more, fair value	2,944	1,516
Available-for-sale securities, 12 months or more, unrealized losses	(18)	(72)
Asset-backed Securities [Member]
Available-for-sale securities, less than 12 months, fair value	2,222	4,734
Available-for-sale securities, less than 12 months, unrealized losses	(5)	(13)
Available-for-sale securities, fair value	3,567	8,164
Available-for-sale securities, unrealized losses	(71)	(114)
Available-for-sale securities, 12 months or more, fair value	1,345	3,430
Available-for-sale securities, 12 months or more, unrealized losses	(66)	(101)
Available-for-sale securities, less than 12 months, fair value	38,460	54,959
Available-for-sale securities, less than 12 months, unrealized losses	(256)	(515)
Available-for-sale securities, fair value	50,680	64,836
Available-for-sale securities, unrealized losses	(488)	(748)
Available-for-sale securities, 12 months or more, fair value	12,220	9,877
Available-for-sale securities, 12 months or more, unrealized losses	$ (232)	$ (233)

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27290-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27337-111563

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Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27337-111563

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-Publisher FASB
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