Loans And Related Allowances For Loan Losses (Narrative) (Details)	12 Months Ended
Dec. 31, 2016 USD ($) loan contract	Dec. 31, 2015 USD ($) 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	$ 13,946,000	$ 15,498,000
Financing receivable, modifications, number of contracts \| loan	24	29
Financing receivable, modifications, recorded investment	$ 9,300,000	$ 14,000,000
Transfers from loans to OREO	6,938,000	1,385,000
Partial Charge Off [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	$ 11,100,000	4,100,000
New TDR [Member]
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts \| contract	7
Reduction of the ALL resulting from new TDRs	$ 7,000
Pre-Existing Troubled Debt Restructuring Loans Remodified After Maturity [Member]
Financing Receivable, Modifications [Line Items]
Financing receivable, modifications, number of contracts \| contract	5
Troubled Debt Restructuring [Member]
Financing Receivable, Modifications [Line Items]
Unused commitments to extend credit	$ 0	11,200
Foreclosure 1-4 Family Real Estate Properties [Member]
Financing Receivable, Modifications [Line Items]
Loans secured by real estate properties in process of foreclosure	500,000	1,800,000
Commercial real estate- non owner-occupied [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	6,381,000	1,308,000
Commercial real estate- all other CRE [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	5,830,000	9,974,000
Transfers from loans to OREO	1,500,000
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	45,000	1,817,000
Transfers from loans to OREO	1,700,000
Commercial and industrial [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	0	185,000
Transfers from loans to OREO	200,000
Residential mortgage- term [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	$ 1,539,000	1,938,000
Financing receivable, modifications, subsequent default, number of contracts \| loan	2
Financing receivable, modifications, subsequent default, recorded investment	$ 100,000	200,000
Transfers from loans to OREO	200,000	100,000
Residential mortgage- home equity [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	151,000	276,000
Consumer [Member]
Financing Receivable, Modifications [Line Items]
Nonaccrual loans subject to partial charge off	$ 0	$ 0

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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
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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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Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

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Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

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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 amount of the write-down related to a troubled debt restructuring.

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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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