Loans And Related Allowances For Loan Losses (Average of Impaired Loans and Related Interest Income by Loan Portfolio Class) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Financing Receivable, Impaired [Line Items]
Average Investment	$ 14,929	$ 16,874	$ 15,076	$ 15,171
Interest income recognized on an accrual basis	64	69	195	219
Interest income recognized on a cash basis		70	4	82
Commercial real estate- non owner-occupied [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	127	201	134	241
Interest income recognized on an accrual basis	3	3	6	9
Commercial real estate- all other CRE [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	3,278	4,773	3,201	4,644
Interest income recognized on an accrual basis	36	37	109	113
Interest income recognized on a cash basis		68		68
Acquisition and development- 1-4 family residential construction [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	276	152	282	232
Interest income recognized on an accrual basis	3	1	9	10
Acquisition and development- All other A&D [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	8,158	8,085	8,243	6,062
Interest income recognized on an accrual basis	3	6	9	12
Interest income recognized on a cash basis			1
Commercial and industrial [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	18	27	16	25
Residential mortgage- term [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	2,565	2,701	2,531	3,082
Interest income recognized on an accrual basis	19	22	62	75
Interest income recognized on a cash basis				10
Residential mortgage- home equity [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	474	928	651	873
Interest income recognized on a cash basis		2	3	4
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	$ 33	$ 7	$ 18	$ 12

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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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