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	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Financing Receivable, Impaired [Line Items]
Average Investment	$ 11,607	$ 15,299	$ 10,224	$ 15,257
Interest income recognized on an accrual basis	62	64	126	131
Interest income recognized on a cash basis		3	5	4
Commercial real estate- non owner-occupied [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	4,689	132	3,165	138
Interest income recognized on an accrual basis	3	1	6	3
Commercial real estate- all other CRE [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	2,982	3,258	3,058	3,182
Interest income recognized on an accrual basis	34	36	69	73
Acquisition and development- 1-4 family residential construction [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	255	282	259	285
Interest income recognized on an accrual basis	3	3	6	6
Acquisition and development- All other A&D [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	611	8,515	599	8,436
Interest income recognized on an accrual basis	3	3	6	6
Interest income recognized on a cash basis				1
Commercial and industrial [Member]
Financing Receivable, Impaired [Line Items]
Average Investment		9		16
Residential mortgage- term [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	2,585	2,450	2,672	2,477
Interest income recognized on an accrual basis	19	21	39	43
Interest income recognized on a cash basis			5
Residential mortgage- home equity [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	474	634	454	709
Interest income recognized on a cash basis		3		3
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	$ 11	$ 19	$ 17	$ 14

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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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