Loans (Impaired Loans) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Financing Receivable, Impaired [Line Items]
Related Allowance	$ 16		$ 16		$ 18
Total, recorded investment	3,051		3,051		1,947
Total, unpaid principal balance	3,141		3,141		2,037
Total, average recorded investment	3,065	$ 9,935	3,043	$ 9,992
Total, interest income recognized	17	7	29	22
Commercial And Industrial [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with no related allowance recorded	35		35		48
Unpaid principal balance with no related allowance recorded	35		35		48
Average recorded investment with no related allowance recorded	37	63	68	81
Interest income recognized with no related allowance recorded	1		2	2
Average recorded investment with an allowance recorded		99		99
Total, recorded investment	35		35		48
Total, unpaid principal balance	35		35		48
Total, average recorded investment	37	162	68	180
Total, interest income recognized	1		2	2
Commercial Mortgages [Member] \| Owner-occupied Loan [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with no related allowance recorded	525		525		531
Unpaid principal balance with no related allowance recorded	608		608		615
Average recorded investment with no related allowance recorded	526	547	539	549
Interest income recognized with no related allowance recorded	6	7	12	11
Average recorded investment with an allowance recorded		7,107		7,130
Total, recorded investment	525		525		531
Total, unpaid principal balance	608		608		615
Total, average recorded investment	526	7,654	539	7,679
Total, interest income recognized	6	7	12	11
Residential Mortgages [Member] \| Closed End Loan [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with no related allowance recorded	1,887		1,887		1,095
Unpaid principal balance with no related allowance recorded	1,894		1,894		1,102
Related Allowance	16		16		18
Average recorded investment with no related allowance recorded	1,894	261	1,929	266
Interest income recognized with no related allowance recorded	2		3
Recorded investment with an allowance recorded	262		262		273
Unpaid principal balance with an allowance recorded	262		262		272
Average recorded investment with an allowance recorded	264	383	276	387
Interest income recognized with an allowance recorded	3		6	9
Total, recorded investment	2,149		2,149		1,368
Total, unpaid principal balance	2,156		2,156		$ 1,374
Total, average recorded investment	2,158	644	2,205	653
Total, interest income recognized	5		9	9
Residential Mortgages [Member] \| Revolving Home Equity [Member]
Financing Receivable, Impaired [Line Items]
Average recorded investment with an allowance recorded		1,475		1,480
Total, average recorded investment		$ 1,475		$ 1,480
Consumer And Other [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with no related allowance recorded	342		342
Unpaid principal balance with no related allowance recorded	342		342
Average recorded investment with no related allowance recorded	344		231
Interest income recognized with no related allowance recorded	5		6
Total, recorded investment	342		342
Total, unpaid principal balance	342		342
Total, average recorded investment	344		231
Total, interest income recognized	$ 5		$ 6

Impaired Financing Receivable, Interest Income (Reversal), Accrual Method

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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)
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-Publisher FASB
-Name Accounting Standards Codification
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