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Fair Values of Financial Instruments - Valuation Methodologies Used for Instruments Measured at Fair Value on Non-Recurring Basis (Details) - Fair Value, Measurements, Nonrecurring - USD ($) $ in Thousands | Dec. 31, 2018 | Dec. 31, 2017
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Significant Unobservable Inputs (Level 3) | Impaired Loans (collateral dependent) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Asset fair value | $ 11,866 | $ 9,576
Significant Unobservable Inputs (Level 3) | Other real estate owned |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Asset fair value | 657 | 859
Fair Value | Impaired Loans (collateral dependent) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Asset fair value | 11,866 | 9,576
Fair Value | Other real estate owned |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Asset fair value | $ 657 | $ 859

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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
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