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, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Financing Receivable, Impaired [Line Items]
Average Investment	$ 12,294	$ 20,257	$ 12,539	$ 21,575
Interest income recognized on an accrual basis	97	122	196	246
Interest income recognized on a cash basis	0	7	129	7
Commercial real estate- non owner-occupied [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	1,258	5,672	813	6,037
Interest income recognized on an accrual basis	3	6	7	12
Interest income recognized on a cash basis	0	0	66	0
Commercial real estate- all other CRE [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	5,726	7,766	6,625	8,658
Interest income recognized on an accrual basis	50	52	99	105
Interest income recognized on a cash basis	0	0	56	0
Acquisition and development- 1-4 family residential construction [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	492	582	457	582
Interest income recognized on an accrual basis	6	6	12	12
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	340	1,818	276	1,860
Interest income recognized on an accrual basis	3	22	6	45
Interest income recognized on a cash basis	0	0	0	0
Commercial and industrial [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	311	290	305	290
Interest income recognized on an accrual basis	5	3	10	6
Interest income recognized on a cash basis	0	0	0	0
Residential mortgage- term [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	3,529	3,860	3,487	3,918
Interest income recognized on an accrual basis	30	33	62	66
Interest income recognized on a cash basis	0	7	0	7
Residential mortgage- home equity [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	614	269	553	230
Interest income recognized on an accrual basis	0	0	0	0
Interest income recognized on a cash basis	0	0	7	0
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	24	0	23	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=84173941&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=84173941&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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