Loans (Impaired Loans) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Impaired [Line Items]
Related Allowance	$ 14	$ 16	$ 18
Total, recorded investment	1,958	3,423	1,947
Total, unpaid principal balance	2,061	3,523	2,037
Total, average recorded investment	2,016	3,503	2,123
Total, interest income recognized	64	62	46
Commercial And Industrial [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with no related allowance recorded		22	48
Unpaid principal balance with no related allowance recorded		22	48
Average recorded investment with no related allowance recorded		48	67
Interest income recognized with no related allowance recorded		3	5
Total, recorded investment		22	48
Total, unpaid principal balance		22	48
Total, average recorded investment		48	67
Total, interest income recognized		3	5
Commercial Mortgages [Member] \| Owner-occupied Loan [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with no related allowance recorded	501	520	531
Unpaid principal balance with no related allowance recorded	585	604	615
Average recorded investment with no related allowance recorded	510	530	654
Interest income recognized with no related allowance recorded	30	25	21
Total, recorded investment	501	520	531
Total, unpaid principal balance	585	604	615
Total, average recorded investment	510	530	654
Total, interest income recognized	30	25	21
Residential Mortgages [Member] \| Closed-end [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with no related allowance recorded	1,039	1,561	1,095
Unpaid principal balance with no related allowance recorded	1,058	1,573	1,102
Related Allowance	14	16	18
Average recorded investment with no related allowance recorded	1,064	1,566	1,122
Interest income recognized with no related allowance recorded	8	5	7
Recorded investment with an allowance recorded	150	253	273
Unpaid principal balance with an allowance recorded	150	253	272
Average recorded investment with an allowance recorded	153	266	280
Interest income recognized with an allowance recorded	7	12	13
Total, recorded investment	1,189	1,814	1,368
Total, unpaid principal balance	1,208	1,826	1,374
Total, average recorded investment	1,217	1,832	1,402
Total, interest income recognized	15	17	$ 20
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		754
Total, recorded investment		743
Total, unpaid principal balance		747
Total, average recorded investment		754
Consumer And Other [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with no related allowance recorded	268	324
Unpaid principal balance with no related allowance recorded	268	324
Average recorded investment with no related allowance recorded	289	339
Interest income recognized with no related allowance recorded	19	17
Total, recorded investment	268	324
Total, unpaid principal balance	268	324
Total, average recorded investment	289	339
Total, interest income recognized	$ 19	$ 17

Impaired Financing Receivable, with No Related Allowance, Interest Income (Reversal), Accrual Method

No definition available.

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- Definition

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+ References

No definition available.

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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
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- Definition

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