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, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Financing Receivable, Impaired [Line Items]
Average Investment	$ 16,874	$ 11,580	$ 15,171	$ 12,539
Interest income recognized on an accrual basis	69	98	219	294
Interest income recognized on a cash basis	70	2	82	131
Commercial real estate- non owner-occupied [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	201	772	241	1,716
Interest income recognized on an accrual basis	3	2	9	9
Interest income recognized on a cash basis				66
Commercial real estate- all other CRE [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	4,773	5,848	4,644	5,495
Interest income recognized on an accrual basis	37	54	113	153
Interest income recognized on a cash basis	68		68	56
Acquisition and development- 1-4 family residential construction [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	152	422	232	475
Interest income recognized on an accrual basis	1	6	10	18
Acquisition and development- All other A&D [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	8,085	274	6,062	350
Interest income recognized on an accrual basis	6	3	12	9
Commercial and industrial [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	27	161	25	327
Interest income recognized on an accrual basis		3		13
Residential mortgage- term [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	2,701	3,537	3,082	3,566
Interest income recognized on an accrual basis	22	30	75	92
Interest income recognized on a cash basis		2	10	2
Residential mortgage- home equity [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	928	544	873	585
Interest income recognized on a cash basis	2		4	7
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Average Investment	$ 7	$ 22	$ 12	$ 25

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5212-111524

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=118936363&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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