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Fair Value (Details Textual) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2018 | Sep. 30, 2018 | Jun. 30, 2018 | Mar. 31, 2018 | Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |
Fair value assets liabilities transfers amount between level 1 and level 2 |  |  |  |  |  |  |  |  | $ 0 | $ 0 |
Impaired loans, unpaid principal balance with allowance recorded | $ 1,897 |  |  |  | $ 1,636 |  |  |  | 1,897 | 1,636 |
Impaired loans, allowance | 276 |  |  |  | 162 |  |  |  | 276 | 162 |
Provision for loan losses | 525 | $ 950 | $ 750 | $ 775 | 400 | $ 950 | $ 950 | $ 1,050 | 3,000 | 3,350 | $ 3,870
Troubled debt restructurings | 5,500 |  |  |  | 5,000 |  |  |  | $ 5,500 | 5,000 |
Other real estate owned measured at fair value less costs to sell |  |  |  |  | 0 |  |  |  |  | 0 |
Write down of other real estate owned |  |  |  |  |  |  |  |  |  | 23 | 36
Maximum maturity period of short term borrowings |  |  |  |  |  |  |  |  | 90 days |  |
Measured Using Present Value of Cash Flows |  |  |  |  |  |  |  |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |
Troubled debt restructurings | 694 |  |  |  | 763 |  |  |  | $ 694 | 763 |
Collateral Dependent Impaired Loans |  |  |  |  |  |  |  |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |  |  |  |  |  |  |  |
Impaired loans, unpaid principal balance with allowance recorded | 1,100 |  |  |  | 851 |  |  |  | 1,100 | 851 | 727
Impaired loans, allowance | $ 227 |  |  |  | $ 109 |  |  |  | 227 | 109 | 173
Provision for loan losses |  |  |  |  |  |  |  |  | $ 180 | $ 272 | $ 139

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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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