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Fair Value (Details Textual) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017 | Dec. 31, 2017
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 | $ 0 | $ 0 |
Impaired loans, unpaid principal balance with allowance recorded | 2,666 |  | 2,666 |  | $ 1,636
Impaired loans, allowance | 318 |  | 318 |  | 162
Provision for loan losses | 950 | 950 | 2,475 | 2,950 |
Troubled debt restructurings | 5,600 |  | $ 5,600 |  | 5,000
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 | 707 |  | $ 707 |  | 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 | 1,900 |  | 1,900 |  | 851
Impaired loans, allowance | 267 |  | 267 |  | $ 109
Provision for loan losses | $ 94 | $ 16 | $ 222 | $ 173 |

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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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