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	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Financing Receivable, Impaired [Line Items]
Average Investment	$ 11,229	$ 14,929	$ 10,465	$ 15,076	$ 13,554
Interest income recognized on an accrual basis	52	64	178	195
Interest income recognized on a cash basis			5	4
Commercial real estate- non owner-occupied [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	4,631	127	3,518	134	131
Interest income recognized on an accrual basis	3	3	9	6
Commercial real estate- all other CRE [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	2,787	3,278	2,984	3,201	3,203
Interest income recognized on an accrual basis	26	36	95	109
Acquisition and development- 1-4 family residential construction [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	249	276	256	282	278
Interest income recognized on an accrual basis	3	3	9	9
Acquisition and development- All other A&D [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	602	8,158	599	8,243	6,709
Interest income recognized on an accrual basis	3	3	9	9
Interest income recognized on a cash basis				1
Commercial and industrial [Member]
Financing Receivable, Impaired [Line Items]
Average Investment		18		16	16
Residential mortgage- term [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	2,500	2,565	2,642	2,531	2,593
Interest income recognized on an accrual basis	17	19	56	62
Interest income recognized on a cash basis			5
Residential mortgage- home equity [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	451	474	449	651	604
Interest income recognized on a cash basis				3
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	$ 9	$ 33	$ 17	$ 18	$ 20

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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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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