Loans And Related Allowances For Loan Losses (Narrative) (Details)	12 Months Ended
Dec. 31, 2018 USD ($) loan contract	Dec. 31, 2017 USD ($) 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
Non consumer loan amount benchmark minimum for annual review by independent reviewer	500,000
Commercial relationship amount benchmark for evaluation	750,000
Maximum commercial loan benchmark for external appraisal	$ 500,000
Past appraisal period benchmark for external appraisal	18 months
Threshold limit for commercial loan appraisal by internal discounted appraisal grid	$ 500,000
Nonaccrual loans subject to partial charge off	$ 4,922,000	$ 7,118,000
Financing receivable, modifications, number of contracts \| loan	16	19
Financing receivable, modifications, recorded investment	$ 4,900,000	$ 6,000,000
Transfers from loans to OREO	534,000	2,060,000
Partial Charge Off [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	$ 300,000	2,100,000
New TDR [Member]
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts \| contract	0
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	300,000	400,000
Commercial real estate- non owner-occupied [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	173,000	3,248,000
Commercial real estate- all other CRE [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	1,968,000	1,205,000
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	147,000	211,000
Commercial and industrial [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	0	378,000
Residential mortgage- term [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	1,911,000	1,466,000
Residential mortgage- home equity [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	713,000	580,000
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	$ 10,000	$ 30,000

Commercial amount benchmark minimum criticized relationships for annual review by independent reviewer.

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Commercial amount benchmark minimum for internal annual review.

+ References

No definition available.

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Commercial amount benchmark minimum for annual review by independent reviewer.

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The minimum period has to be taken in past appraisal for conducting the review by external team.

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No definition available.

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Commercial amount benchmark for appraisal by internal generated discounted appraisal grid.

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Commercial amount benchmark minimum for review by external appraisal team.

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Non Consumer loan amount benchmark minimum for annual review by independent reviewer.

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No definition available.

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- Definition

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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No definition available.

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
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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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- Definition

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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- Definition

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

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-Name Accounting Standards Codification
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Unused amount of commitments to extend credit to customers.

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