Represents the percentage of indemnification.

No definition available.

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- Definition

Period of time loans are considered delinquent and past due.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Period of time in delinquency after loan is considered impaired.

+ References

No definition available.

+ Details

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- Definition

Maximum amount of principal balance of loans subject to reserve, based on historical loss rates.

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Minimum amount of principal for loans to be reviewed that are deemed to be impaired.

+ References

No definition available.

+ Details

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- Definition

Minimum amount of principal balance of loans subject to reserve, based on collateral and net present value.

+ References

No definition available.

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- Definition

Represents the number of days used to calculate loan allowance.

+ References

No definition available.

+ Details

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66022249&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Cost of the investment.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=63488139&loc=d3e12121-115841

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Balance Type:	debit
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- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980

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Data Type:	xbrli:durationItemType
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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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- Definition

The amount of a reclassification adjustment made to prior period financial statement amounts.

+ References

No definition available.

+ Details

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Difference between the carrying amount of assets and liabilities in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the variable interest entity (VIE) and the reporting entity's maximum exposure to loss as a result of its involvement with the VIE, where the reporting entity is not the VIE's primary beneficiary.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=77990344&loc=d3e5728-111685

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

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Note 1 - Basis of Presentation and Significant Accounting Policies (Details Textual) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Number of Operating Segments		1
Equity Method Investments		$ 0	$ 0
Variable Interest Entity, Nonconsolidated, Comparison of Carrying Amount of Assets and Liabilities to Maximum Loss Exposure		823	1,140
Minimum Principal Balance of Loans for Quarterly Rating Review		$ 250
Loan Payments Delinquency Period Beyond which Loan is Considered Non Accrual		90 days
Minimum Principal Balance of Loans Subject to Reserve Based on Collateral or Net Present Value Method		$ 250
Maximum Principal Balance of Loans Subject to Reserve Based on Historical Loss Rate		$ 250
Indemnification Percentage		80.00%
Lessee, Operating Lease, Term of Contract		20 years
Reclassification from AOCI to Retained Earnings [Member] \| Scenario, Forecast [Member] \| Twelve Months Ended December 31, 2017 [Member]
Prior Period Reclassification Adjustment	$ 244
Land Improvements [Member]
Property, Plant and Equipment, Useful Life		20 years
Other Loan [Member]
Number Of Period Used To Calculate Allowance For Loans		120 days
Consumer Loan [Member]
Number Of Period Used To Calculate Allowance For Loans		120 days
Consumer Loan [Member] \| Unsecured Loan [Member]
Number Of Period Used To Calculate Allowance For Loans		90 days
Consumer Loan [Member] \| Residential Real Estate [Member]
Number Of Period Used To Calculate Allowance For Loans		180 days
Minimum [Member]
Loan Delinquent Period		30 days
Minimum [Member] \| Furniture and Fixtures [Member]
Property, Plant and Equipment, Useful Life		5 years
Minimum [Member] \| Equipment, Computer Hardware and Software [Member]
Property, Plant and Equipment, Useful Life		3 years
Minimum [Member] \| Building and Building Improvements [Member]
Property, Plant and Equipment, Useful Life		10 years
Maximum [Member] \| Furniture and Fixtures [Member]
Property, Plant and Equipment, Useful Life		10 years
Maximum [Member] \| Equipment, Computer Hardware and Software [Member]
Property, Plant and Equipment, Useful Life		5 years
Maximum [Member] \| Building and Building Improvements [Member]
Property, Plant and Equipment, Useful Life		40 years
Investment in Federal Home Loan Bank (FHLB) and Federal Reserve Bank (FRB) Stock [Member]
Investment Owned, at Cost		$ 9,900	$ 10,600