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Fair Value (Narrative) (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Loans held-for-sale, fair value |  | $ 4,263,000 | $ 6,719,000
Contractual principal balance of loans held-for-sale |  | 4,231,000 | 6,576,000
Difference in amount of loan held-for-sale |  | 32,000 | 143,000
Impaired loans, carrying amount | [1] | 6,757,000 | 9,293,000
Valuation allowance for loans losses |  | 1,826,000 | 2,234,000
Other real estate carried at fair value less cost to sell |  | 0 | 0
Other real estate, adjustments to carrying value less costs to sell charged to earnings |  | 0 | 0
Impaired Loans |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Impaired loans, carrying amount |  | 6,561,000 | 9,020,000
Valuation allowance for loans losses |  | 1,823,000 | 2,228,000
Increase (decrease) in provision for loan losses |  | (411,000) | 1,973,000
Obligations of State and Political Subdivisions |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Other changes in fair value |  | (69,000) | (60,000)
Fair Value, Measurements, Recurring |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Securities |  | 812,611,000 | 740,641,000
Fair Value, Measurements, Recurring | Obligations of State and Political Subdivisions |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Securities |  | 294,533,000 | 273,309,000
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Securities |  | 4,991,000 | 5,649,000
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Obligations of State and Political Subdivisions |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |  |
Securities |  | $ 4,991,000 | $ 5,649,000
[1] | Unpaid Principal Balance is the remaining contractual payments gross of partial charge-offs and discounts.

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