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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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Amount, before accumulated depreciation, of real estate investment by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate. Excludes real estate not held as investment or interest.

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