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, 2017	Mar. 31, 2016
Financing Receivable, Impaired [Line Items]
Average Investment	$ 22,691	$ 25,147
Interest income recognized on an accrual basis	124	123
Interest income recognized on a cash basis	0	4
Commercial real estate- non owner-occupied [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	6,366	1,597
Interest income recognized on an accrual basis	6	6
Interest income recognized on a cash basis	0	0
Commercial real estate- all other CRE [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	9,320	13,093
Interest income recognized on an accrual basis	53	37
Interest income recognized on a cash basis	0	0
Acquisition and development- 1-4 family residential construction [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	582	700
Interest income recognized on an accrual basis	6	8
Interest income recognized on a cash basis	0	0
Acquisition and development- All other A&D [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	1,891	3,869
Interest income recognized on an accrual basis	23	24
Interest income recognized on a cash basis	0	0
Commercial and industrial [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	290	1,071
Interest income recognized on an accrual basis	3	9
Interest income recognized on a cash basis	0	0
Residential mortgage- term [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	4,018	4,519
Interest income recognized on an accrual basis	33	39
Interest income recognized on a cash basis	0	4
Residential mortgage- home equity [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	224	298
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	0	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=49124121&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=49124121&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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