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Note 4 - Fair Value Disclosure Measurements - Additional Quantitative Information about Assets Measured at Fair Value on Non-recurring Basis (Details) - Fair Value, Measurements, Nonrecurring [Member] - Fair Value, Inputs, Level 3 [Member] - USD ($) $ in Thousands | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2017 | Dec. 31, 2016
Impaired Loans [Member] | Appraisal Adjustments [Member] |  |  |
Fair value estimate |  | $ 3,183 | $ 1,570
Valuation Techniques / Unobservable Input | [1],[2] | Appraisal of collateral / Appraisal adjustments | Appraisal of collateral / appraisal adjustments
Impaired Loans [Member] | Appraisal Adjustments [Member] | Minimum [Member] |  |  |
Discount rate |  | 3.30% | 0.00%
Impaired Loans [Member] | Appraisal Adjustments [Member] | Maximum [Member] |  |  |
Discount rate |  | 8.30% | 59.70%
Impaired Loans [Member] | Appraisal Adjustments [Member] | Weighted Average [Member] |  |  |
Discount rate |  | 5.10% | 28.20%
Impaired Loans [Member] | Income Approach Valuation Technique [Member] |  |  |
Fair value estimate |  |  | $ 4,928
Valuation Techniques / Unobservable Input |  |  | Discounted cash flow / discount rate
Impaired Loans [Member] | Income Approach Valuation Technique [Member] | Minimum [Member] |  |  |
Discount rate |  |  | 3.10%
Impaired Loans [Member] | Income Approach Valuation Technique [Member] | Maximum [Member] |  |  |
Discount rate |  |  | 7.00%
Impaired Loans [Member] | Income Approach Valuation Technique [Member] | Weighted Average [Member] |  |  |
Discount rate |  |  | 5.10%
Other Real Estate Owned [Member] | Appraisal Adjustments [Member] |  |  |
Fair value estimate |  | $ 88 | $ 511
Valuation Techniques / Unobservable Input | [1],[2] | Appraisal of collateral / Appraisal adjustments | Appraisal of collateral / appraisal adjustments
Other Real Estate Owned [Member] | Appraisal Adjustments [Member] | Minimum [Member] |  |  |
Discount rate |  | 0.00% | 0.00%
Other Real Estate Owned [Member] | Appraisal Adjustments [Member] | Weighted Average [Member] |  |  |
Discount rate |  | 10.00% | 10.00%
[1] | Appraisals may be adjusted by management for qualitative factors such as economic conditions and estimated liquidation expenses. The range and weighted average of liquidation expenses and other appraisal adjustments are presented as a percent of the appraisal.
[2] | Fair value is generally determined through independent appraisals of the underlying collateral, which generally include various level 3 inputs which are not identifiable, less any associated allowance.

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- Definition This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a nonrecurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. + References No definition available. + Details
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- Definition Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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- Definition Description of the inputs and valuation technique(s) used to measure fair value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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