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, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Financing Receivable, Impaired [Line Items]
Average Investment	$ 28,467	$ 23,724	$ 27,248	$ 24,077
Interest income recognized on an accrual basis	164	172	287	343
Interest income recognized on a cash basis	4	29	8	30
Commercial real estate- non owner-occupied [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	5,916	4,088	4,513	4,224
Interest income recognized on an accrual basis	41	38	47	78
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	12,568	7,574	12,692	7,533
Interest income recognized on an accrual basis	43	28	80	55
Interest income recognized on a cash basis	4	7	4	8
Acquisition and development- 1-4 family residential construction [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	641	746	661	760
Interest income recognized on an accrual basis	7	9	15	18
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	2,988	5,245	3,257	5,417
Interest income recognized on an accrual basis	24	31	48	63
Interest income recognized on a cash basis	0	0	0	0
Commercial and industrial [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	1,121	1,495	1,106	1,617
Interest income recognized on an accrual basis	10	24	19	47
Interest income recognized on a cash basis	0	18	0	18
Residential mortgage- term [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	4,885	4,181	4,695	4,146
Interest income recognized on an accrual basis	39	42	78	82
Interest income recognized on a cash basis	0	2	4	2
Residential mortgage- home equity [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	348	388	324	373
Interest income recognized on an accrual basis	0	0	0	0
Interest income recognized on a cash basis	0	2	0	2
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	0	7	0	7
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=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.

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+ References

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