Note 3 - Securities (Details Textual) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Securities Held as Collateral, at Fair Value	$ 61.6	$ 62.6
Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions, Total	155	138
Residential Mortgage Backed Securities and Collateralized Mortgage Obligations [Member]
Available for Sale Securities, Percent of Portfolio Guaranteed	61.00%	56.00%
Commercial Mortgage Backed Securities [Member]
Available for Sale Securities, Percent of Portfolio Guaranteed	90.00%	90.00%

Represents the percent of portfolio of available-for-sale securities that is guaranteed by government sponsored enterprises.

No definition available.

+ Details

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- Definition

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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- Definition

The carrying amount (fair value) as of the balance sheet date of securities held that had been pledged by counterparties under financing and lending arrangements, pursuant to which the entity has the right by agreement or custom to sell or re-pledge such securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5086-111524

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- Details

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