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Note 14 - Financial Instruments with Off-Balance Sheet Risk - Financial Instruments Outstanding Representing Credit Risk (Details) - USD ($) $ in Thousands | Dec. 31, 2017 | Dec. 31, 2016
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Commitments to Extend Credit [Member] |  |
Off balance sheet liability, amount | $ 161,222 | $ 130,252
Standby Letters of Credit 1 [Member] |  |
Off balance sheet liability, amount | 16,351 | 20,499
Interest Rate Lock Commitments [Member] |  |
Off balance sheet liability, amount | $ 14,130 | $ 17,526

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- Definition The fair value of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611 + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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- Details
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Data Type: | na
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- Details
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Data Type: | na
Balance Type: |
Period Type: |

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- Details
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Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |