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, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Financing Receivable, Impaired [Line Items]
Average Investment	$ 20,257	$ 28,467	$ 21,575	$ 27,248
Interest income recognized on an accrual basis	122	164	246	287
Interest income recognized on a cash basis	7	4	7	8
Commercial real estate- non owner-occupied [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	5,672	5,916	6,037	4,513
Interest income recognized on an accrual basis	6	41	12	47
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	7,766	12,568	8,658	12,692
Interest income recognized on an accrual basis	52	43	105	80
Interest income recognized on a cash basis	0	4	0	4
Acquisition and development- 1-4 family residential construction [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	582	641	582	661
Interest income recognized on an accrual basis	6	7	12	15
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	1,818	2,988	1,860	3,257
Interest income recognized on an accrual basis	22	24	45	48
Interest income recognized on a cash basis	0	0	0	0
Commercial and industrial [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	290	1,121	290	1,106
Interest income recognized on an accrual basis	3	10	6	19
Interest income recognized on a cash basis	0	0	0	0
Residential mortgage- term [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	3,860	4,885	3,918	4,695
Interest income recognized on an accrual basis	33	39	66	78
Interest income recognized on a cash basis	7	0	7	4
Residential mortgage- home equity [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	269	348	230	324
Interest income recognized on an accrual basis	0	0	0	0
Interest income recognized on a cash basis	0	0	0	0
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	0	0	0	0
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=66008989&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=66008989&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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