Note 2 - Investment Securities - Available For Sale Securities in Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Securities Available for Sale, Total Fair Value	$ 53,795	$ 69,591
Securities Available for Sale, Total Unrealized Losses	(946)	(3,216)
Securities Available for Sale, Less than 12 Months Fair Value	36,570	37,086
Securities Available for Sale, Less than 12 Months Unrealized Losses	(213)	(693)
Securities Available for Sale, 12 Months or Longer Fair Value	17,225	32,505
Securities Available for Sale, 12 Months or Longer Unrealized Losses	(733)	(2,523)
US Treasury Securities [Member]
Securities Available for Sale, Total Fair Value	16,980
Securities Available for Sale, Total Unrealized Losses	(13)
Securities Available for Sale, Less than 12 Months Fair Value	16,980
Securities Available for Sale, Less than 12 Months Unrealized Losses	(13)
Securities Available for Sale, 12 Months or Longer Fair Value
Securities Available for Sale, 12 Months or Longer Unrealized Losses
US States and Political Subdivisions Debt Securities [Member]
Securities Available for Sale, Total Fair Value	10,841	24,967
Securities Available for Sale, Total Unrealized Losses	(98)	(586)
Securities Available for Sale, Less than 12 Months Fair Value	10,101	24,252
Securities Available for Sale, Less than 12 Months Unrealized Losses	(64)	(527)
Securities Available for Sale, 12 Months or Longer Fair Value	740	715
Securities Available for Sale, 12 Months or Longer Unrealized Losses	(34)	(59)
Single Issue Trust Preferred Securities [Member]
Securities Available for Sale, Total Fair Value	8,943	19,939
Securities Available for Sale, Total Unrealized Losses	(417)	(2,165)
Securities Available for Sale, Less than 12 Months Fair Value
Securities Available for Sale, Less than 12 Months Unrealized Losses
Securities Available for Sale, 12 Months or Longer Fair Value	8,943	19,939
Securities Available for Sale, 12 Months or Longer Unrealized Losses	(417)	(2,165)
Mortgage-backed Agency Securities [Member]
Securities Available for Sale, Total Fair Value	17,031	24,685
Securities Available for Sale, Total Unrealized Losses	(418)	(465)
Securities Available for Sale, Less than 12 Months Fair Value	9,489	12,834
Securities Available for Sale, Less than 12 Months Unrealized Losses	(136)	(166)
Securities Available for Sale, 12 Months or Longer Fair Value	7,542	11,851
Securities Available for Sale, 12 Months or Longer Unrealized Losses	$ (282)	$ (299)

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=82897076&loc=d3e27290-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 320
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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.

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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=82897076&loc=d3e27337-111563

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