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	6 Months Ended
Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Financing Receivable, Impaired [Line Items]
Average Investment	$ 23,724	$ 29,838	$ 24,077	$ 30,998
Interest income recognized on an accrual basis	172	167	343	373
Interest income recognized on a cash basis	29	86	30	99
Commercial real estate- non owner-occupied [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	4,088	1,068	4,224	1,105
Interest income recognized on an accrual basis	38	4	78	11
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	7,574	9,624	7,533	9,936
Interest income recognized on an accrual basis	28	40	55	81
Interest income recognized on a cash basis	7	43	8	44
Acquisition and development- 1-4 family residential construction [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	746	1,549	760	1,919
Interest income recognized on an accrual basis	9	11	18	25
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	5,245	8,329	5,417	8,567
Interest income recognized on an accrual basis	31	35	63	96
Interest income recognized on a cash basis	0	0	0	0
Commercial and industrial [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	1,495	2,040	1,617	2,126
Interest income recognized on an accrual basis	24	23	47	49
Interest income recognized on a cash basis	18	0	18	2
Residential mortgage- term [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	4,181	6,489	4,146	6,648
Interest income recognized on an accrual basis	42	53	82	107
Interest income recognized on a cash basis	2	43	2	52
Residential mortgage- home equity [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	388	739	373	686
Interest income recognized on an accrual basis	0	1	0	4
Interest income recognized on a cash basis	2	0	2	1
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	7	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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- 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=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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