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, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Financing Receivable, Impaired [Line Items]
Average Investment	$ 11,580	$ 20,245	$ 12,539	$ 21,467
Interest income recognized on an accrual basis	98	122	294	368
Interest income recognized on a cash basis	2	1	131	8
Commercial real estate- non owner-occupied [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	772	6,144	1,716	6,255
Interest income recognized on an accrual basis	2	6	9	18
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	5,848	7,308	5,495	8,314
Interest income recognized on an accrual basis	54	52	153	157
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	422	582	475	582
Interest income recognized on an accrual basis	6	6	18	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	274	1,812	350	1,851
Interest income recognized on an accrual basis	3	23	9	68
Interest income recognized on a cash basis	0	0	0	0
Commercial and industrial [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	161	496	327	393
Interest income recognized on an accrual basis	3	3	13	9
Interest income recognized on a cash basis	0	0	0	0
Residential mortgage- term [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	3,537	3,654	3,566	3,836
Interest income recognized on an accrual basis	30	32	92	98
Interest income recognized on a cash basis	2	1	2	8
Residential mortgage- home equity [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	544	249	585	236
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	22	0	25	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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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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