Loans (Impaired Loans) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Financing Receivable, Impaired [Line Items]
Related Allowance	$ 50		$ 50		$ 16
Total, recorded investment	2,225		2,225		3,423
Total, unpaid principal balance	2,328		2,328		3,523
Total, average recorded investment	2,245	$ 5,424	2,285	$ 5,460
Total, interest income recognized	11	16	33	45
Commercial And Industrial [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with no related allowance recorded	2		2		22
Unpaid principal balance with no related allowance recorded	2		2		22
Related Allowance	36		36
Average recorded investment with no related allowance recorded	5	55	11	82
Interest income recognized with no related allowance recorded			1	2
Recorded investment with an allowance recorded	71		71
Unpaid principal balance with an allowance recorded	71		71
Average recorded investment with an allowance recorded	74		72
Total, recorded investment	73		73		22
Total, unpaid principal balance	73		73		22
Total, average recorded investment	79	55	83	82
Total, interest income recognized			1	2
Commercial Mortgages [Member] \| Other Loan [Member]
Financing Receivable, Impaired [Line Items]
Average recorded investment with no related allowance recorded		2,777		2,800
Total, average recorded investment		2,777		2,800
Commercial Mortgages [Member] \| Owner-occupied Loan [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with no related allowance recorded	506		506		520
Unpaid principal balance with no related allowance recorded	589		589		604
Average recorded investment with no related allowance recorded	508	523	513	534
Interest income recognized with no related allowance recorded	8	6	23	18
Total, recorded investment	506		506		520
Total, unpaid principal balance	589		589		604
Total, average recorded investment	508	523	513	534
Total, interest income recognized	8	6	23	18
Residential Mortgages [Member] \| Closed-end [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with no related allowance recorded	1,216		1,216		1,561
Unpaid principal balance with no related allowance recorded	1,236		1,236		1,573
Related Allowance	14		14		16
Average recorded investment with no related allowance recorded	1,223	718	1,241	751
Interest income recognized with no related allowance recorded	2	1	4	4
Recorded investment with an allowance recorded	152		152		253
Unpaid principal balance with an allowance recorded	152		152		253
Average recorded investment with an allowance recorded	153	259	153	270
Interest income recognized with an allowance recorded	1	3	5	9
Total, recorded investment	1,368		1,368		1,814
Total, unpaid principal balance	1,388		1,388		1,826
Total, average recorded investment	1,376	977	1,394	1,021
Total, interest income recognized	3	4	9	13
Residential Mortgages [Member] \| Revolving Home Equity [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with no related allowance recorded					743
Unpaid principal balance with no related allowance recorded					747
Average recorded investment with no related allowance recorded		756		757
Total, recorded investment					743
Total, unpaid principal balance					747
Total, average recorded investment		756		757
Consumer And Other [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with no related allowance recorded	278		278		324
Unpaid principal balance with no related allowance recorded	278		278		324
Average recorded investment with no related allowance recorded	282	336	295	266
Interest income recognized with no related allowance recorded		6		12
Total, recorded investment	278		278		324
Total, unpaid principal balance	278		278		$ 324
Total, average recorded investment	$ 282	336	$ 295	266
Total, interest income recognized		$ 6		$ 12

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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.

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