Note 2 - Fair Value of Financial Instruments (Details Textual) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Selling Costs, Percentage			10.00%
Impaired Financing Receivable, Related Allowance	$ 90		$ 90		$ 94
Other Real Estate, Ending Balance	822		822		822
Other Real Estate, Gross	2,217		2,217		2,217
Real Estate Owned, Valuation Allowance, Ending Balance	1,395		1,395		1,395
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate, Write-down or Reserve, Amount	0	$ 0	0	$ 0
Collateral Dependent Loans [Member]
Impaired Financing Receivable, with Related Allowance, Recorded Investment	0		0		972
Provision for Loan Losses Expensed		$ 0	0	221	0
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	$ 0		$ 0	$ 1,011	0
Impaired Financing Receivable, Related Allowance					$ 0

The gross caryring amount of other real estate not separately disclosed.

No definition available.

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- Definition

The percent selling cost makes up.

+ References

No definition available.

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- Definition

Reflects the amount of the write-down related to a troubled debt restructuring.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

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- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
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- Definition

Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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- Definition

Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(4))
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- Definition

Amount of expense related to loss from loan transactions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
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- Definition

For each period for which an income statement is required, disclosure of the changes in the allowance, including balances at end of period.

+ References

+ Details

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- Definition

Amount of write-down or reserve recognized in the income statement on real estate investments for entities with a substantial portion of business acquiring and holding investment real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 970
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-28(Footnote 5))
-URI http://asc.fasb.org/extlink&oid=6590653&loc=d3e638233-123024

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