Note 4 - Securities (Details Textual) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Dec. 31, 2016
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	83		83		119
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net		$ 546	$ 0	$ 546
Subordinated Debt [Member]
Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net		$ 546

The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 8B
-URI http://asc.fasb.org/extlink&oid=82897076&loc=SL6284393-111563

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration