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	9 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Financing Receivable, Impaired [Line Items]
Average Investment	$ 24,308	$ 28,380	$ 24,068	$ 30,453
Interest income recognized on an accrual basis	167	162	510	535
Interest income recognized on a cash basis	2	29	32	128
Commercial real estate- non owner-occupied [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	4,607	2,591	4,314	1,890
Interest income recognized on an accrual basis	39	17	117	28
Interest income recognized on a cash basis	0	0	0	0
Commercial real estate- all other CRE [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	7,935	8,506	7,626	9,497
Interest income recognized on an accrual basis	34	35	89	116
Interest income recognized on a cash basis	0	23	8	67
Acquisition and development- 1-4 family residential construction [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	701	1,016	745	1,690
Interest income recognized on an accrual basis	8	9	26	34
Interest income recognized on a cash basis	0	0	0	0
Acquisition and development- All other A&D [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	5,091	7,540	5,311	8,108
Interest income recognized on an accrual basis	31	33	94	129
Interest income recognized on a cash basis	0	0	0	0
Commercial and industrial [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	1,253	1,905	1,471	2,065
Interest income recognized on an accrual basis	13	21	60	70
Interest income recognized on a cash basis	0	0	18	2
Residential mortgage- term [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	4,400	6,225	4,245	6,552
Interest income recognized on an accrual basis	42	47	124	154
Interest income recognized on a cash basis	2	3	4	55
Residential mortgage- home equity [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	321	597	349	640
Interest income recognized on an accrual basis	0	0	0	4
Interest income recognized on a cash basis	0	3	2	4
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	0	0	7	11
Interest income recognized on an accrual basis	0	0	0	0
Interest income recognized on a cash basis	$ 0	$ 0	$ 0	$ 0

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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://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=35738203&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=35738203&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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