Loans and Related Allowance for Loan Losses (Average of Impaired Loans and Related Interest Income by Loan Portfolio Class) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Financing Receivable, Impaired [Line Items]
Average Investment	$ 13,498	$ 22,691
Interest income recognized on an accrual basis	99	124
Interest income recognized on a cash basis	129	0
Commercial real estate- non owner-occupied [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	2,660	6,366
Interest income recognized on an accrual basis	4	6
Interest income recognized on a cash basis	66	0
Commercial real estate- all other CRE [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	5,142	9,320
Interest income recognized on an accrual basis	49	53
Interest income recognized on a cash basis	56	0
Acquisition and development- 1-4 family residential construction [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	527	582
Interest income recognized on an accrual basis	6	6
Interest income recognized on a cash basis	0	0
Acquisition and development- All other A&D [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	426	1,891
Interest income recognized on an accrual basis	3	23
Interest income recognized on a cash basis	0	0
Commercial and industrial [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	493	290
Interest income recognized on an accrual basis	5	3
Interest income recognized on a cash basis	0	0
Residential mortgage- term [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	3,595	4,018
Interest income recognized on an accrual basis	32	33
Interest income recognized on a cash basis	0	0
Residential mortgage- home equity [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	627	224
Interest income recognized on an accrual basis	0	0
Interest income recognized on a cash basis	7	0
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	28	0
Interest income recognized on an accrual basis	0	0
Interest income recognized on a cash basis	$ 0	$ 0

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No definition available.

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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=84173941&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=84173941&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.

+ References

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+ References

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