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, 2017	Dec. 31, 2016
Financing Receivable, Impaired [Line Items]
Average Investment	$ 20,172	$ 27,028
Interest income recognized on an accrual basis	482	640
Interest income recognized on a cash basis	38	24
Commercial real estate- non owner-occupied [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	5,727	6,076
Interest income recognized on an accrual basis	24	131
Interest income recognized on a cash basis	30	0
Commercial real estate- all other CRE [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	7,743	11,802
Interest income recognized on an accrual basis	205	187
Interest income recognized on a cash basis	0	8
Acquisition and development- 1-4 family residential construction [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	571	629
Interest income recognized on an accrual basis	24	27
Interest income recognized on a cash basis	0	0
Acquisition and development- All other A&D [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	1,571	2,735
Interest income recognized on an accrual basis	85	95
Interest income recognized on a cash basis	0	0
Commercial and industrial [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	448	934
Interest income recognized on an accrual basis	13	37
Interest income recognized on a cash basis	0	0
Residential mortgage- term [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	3,792	4,580
Interest income recognized on an accrual basis	131	163
Interest income recognized on a cash basis	8	16
Residential mortgage- home equity [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	305	272
Interest income recognized on an accrual basis	0	0
Interest income recognized on a cash basis	0	0
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	15	0
Interest income recognized on an accrual basis	0	0
Interest income recognized on a cash basis	$ 0	$ 0

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- Definition

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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=66008989&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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+ References

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