Loans And Related Allowances For Loan Losses (Average of Impaired Loans and Related Interest Income by Loan Portfolio Class) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Impaired [Line Items]
Average Investment	$ 13,554	$ 15,170
Interest income recognized on an accrual basis	259	287
Interest income recognized on a cash basis	5	87
Commercial real estate- non owner-occupied [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	131	222
Interest income recognized on an accrual basis	9	12
Commercial real estate- all other CRE [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	3,203	4,322
Interest income recognized on an accrual basis	144	149
Interest income recognized on a cash basis		73
Acquisition and development- 1-4 family residential construction [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	278	244
Interest income recognized on an accrual basis	12	11
Acquisition and development- All other A&D [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	6,709	6,505
Interest income recognized on an accrual basis	12	19
Interest income recognized on a cash basis	1
Commercial and industrial [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	16	26
Residential mortgage- term [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	2,593	2,971
Interest income recognized on an accrual basis	82	96
Interest income recognized on a cash basis		10
Residential mortgage- home equity [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	604	870
Interest income recognized on a cash basis	4	4
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	$ 20	$ 10

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Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5258-111524

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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

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