Note 3 - Securities (Details Textual) - USD ($) $ in Millions	Sep. 30, 2018	Dec. 31, 2017
Securities Held as Collateral, at Fair Value	$ 70.1	$ 62.6
Debt Securities, Available-for-sale, Unrealized Loss Position, Number of Positions	174	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 investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-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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