Loans And Related Allowances For Loan Losses (Modification of Troubled Debt Restructuring by Class) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2019 USD ($) loan contract	Dec. 31, 2018 USD ($) loan contract
Financing Receivable, Modifications [Line Items]
Number of Contracts \| loan	15	16
Recorded Investment	$ 4,200	$ 4,900
Temporary Rate Modification [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	2
Recorded Investment	$ 244
Temporary Rate Modification [Member] \| Residential mortgage- term [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	2
Recorded Investment	$ 244
Extension Of Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		2
Recorded Investment		$ 566
Extension Of Maturity [Member] \| Commercial real estate- all other CRE [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		1
Recorded Investment		$ 179
Extension Of Maturity [Member] \| Acquisition and development- 1-4 family residential construction [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		1
Recorded Investment		$ 387
Modification Of Payment And Other Terms [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	2	4
Recorded Investment	$ 470	$ 793
Modification Of Payment And Other Terms [Member] \| Commercial real estate- non owner-occupied [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		3
Recorded Investment		$ 358
Modification Of Payment And Other Terms [Member] \| Acquisition and development- All other A&D [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1
Recorded Investment	$ 227
Modification Of Payment And Other Terms [Member] \| Residential mortgage- term [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1	1
Recorded Investment	$ 243	$ 435

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

+ References

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Amount of financing receivable modified as troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=118939409&loc=d3e18845-111554

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