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Note 4 - Loans and Allowance for Loan Losses (Details Textual) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
Number of Portfolio Segments | 8 |
Number of Loans, Related Party | 0 | 0
Financing Receivable, Recorded Investment, Nonaccrual Status | $ 2,037 | $ 2,148
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans | 6 | 19
Interest Income Recorded | 1 | 3
Financing Receivable, Restructuring Recorded Investment With Nonaccrual Status | 100 | 100
Financing Receivable, Modifications, Recorded Investment | $ 0 | $ 0
Financing Receivable, Modifications, Subsequent Default, Number of Contracts | 0 | 0
Loans Modified in a Troubled Debt Restructuring, Individually Evaluated for Impairment, Principal Balance, Threshold | $ 500 |
Allowance for Credit Losses, Change in Method of Calculating Impairment | 2 | $ 2
Minimum [Member] |  |
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest | 500 |
Minimum [Member] | ALC [Member] |  |
Loans and Leases Receivable, Nonperforming, Nonaccrual of Interest | 100 |
Related Party Loan [Member] |  |
Loans and Leases Receivable, Related Parties, Ending Balance | 400 | 500
Loans and Leases Receivable, Related Parties, Proceeds | $ 100 | $ 11
Real Estate [Member] |  |
Percentage of Loan Portfolio | 55.00% | 54.00%

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- Definition Represents the amount of financing receivable restructuring recorded investment with nonaccrual status. + References No definition available. + Details
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- Definition Represents the threshold used in determining which loans that have been modified in a troubled debt restructuring are considered impaired and evaluated individually for impairment. All such loans with a principal balance above this threshold are considered impaired and evaluated individually for impairment. + References No definition available. + Details
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- Definition Indicates the number of loans made to related party during the period. + References No definition available. + Details
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- Definition Represents the number of portfolio segments into which the Company has divided the loan portfolio as of the balance sheet date. + References No definition available. + Details
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- Definition Amount of allowance for credit losses related to receivables which had been measured under a general allowance for credit losses methodology that are now identified as troubled debt restructurings. + References No definition available. + Details
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- Definition The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings. + 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 + Details
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- Definition Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524 + Details
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- Definition Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524 + Details
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- Definition Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 40 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18794-111554 + Details
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- Definition Reflects the carrying amount of loans deemed to be questionable as to collection on which no interest is continuing to be recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524 + Details
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- Definition For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 850 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.7(e)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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