Loans And Related Allowances For Loan Losses (Narrative) (Details)	12 Months Ended
Dec. 31, 2017 USD ($) loan contract	Dec. 31, 2016 USD ($) loan
Financing Receivable, Modifications [Line Items]
Commercial amount benchmark minimum for internal annual review	$ 500,000
Commercial amount benchmark minimum for annual review by independent reviewer	1,000,000
Commercial relationship amount benchmark for evaluation	750,000
Nonaccrual loans subject to partial charge off	$ 7,118,000	$ 13,946,000
Financing receivable, modifications, number of contracts \| loan	19	24
Financing receivable, modifications, recorded investment	$ 6,000,000	$ 9,300,000
Transfers from loans to OREO	2,060,000	6,938,000
Partial Charge Off [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	$ 7,400,000	11,100,000
New TDR [Member]
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts \| contract	0
Pre-Existing Troubled Debt Restructuring Loans Remodified After Maturity [Member]
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts \| contract	3
Troubled Debt Restructuring [Member]
Financing Receivable, Modifications [Line Items]
Unused commitments to extend credit	$ 0	0
Foreclosure 1-4 Family Real Estate Properties [Member]
Financing Receivable, Modifications [Line Items]
Loans secured by real estate properties in process of foreclosure	400,000	500,000
Commercial real estate- non owner-occupied [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	3,248,000	6,381,000
Commercial real estate- all other CRE [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	1,205,000	5,830,000
Acquisition and development- 1-4 family residential construction [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	0	0
Acquisition and development- All other A&D [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	211,000	45,000
Commercial and industrial [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	378,000	0
Residential mortgage- term [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	1,466,000	1,539,000
Residential mortgage- home equity [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	580,000	151,000
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	$ 30,000	$ 0

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Commercial amount benchmark minimum for internal annual review.

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Commerical amount benchmark minimum for annual review by independent reviewer.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Number of financing receivables that have been modified by troubled debt restructurings.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

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Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

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Reflects the aggregate value of loans, trade receivables, securities and financial instruments that serve as collateral for obligations arising from a transfer of financial assets recorded as a secured borrowing.

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Value transferred from mortgage loans to real estate owned (REO) in noncash transactions.

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Unused amount of commitments to extend credit to customers.

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