Loans and Allowance for Credit Losses on Loans (Summary of Impaired Loan Balances and Associated Allowance by Portfolio Segment) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	$ 2,841	$ 4,476
Unpaid principal balance with related allowance recorded	2,841	4,476
Average recorded investment with related allowance recorded	3,933	5,921
Interest income recognized with related allowance recorded	121	138
Recorded investment without related allowance recorded	1,637	2,450
Unpaid principal balance without related allowance recorded	2,426	3,001
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	1,993	5,368
Interest income recognized without related allowance recorded	41	55
Recorded investment, total impaired loans	4,478	6,926
Unpaid principal balance, total impaired loans	5,267	7,477
Related allowance, total impaired loans	463	824
Average recorded investment, total impaired loans	5,926	11,289
Interest income recognized, total impaired loans	162	193
Residential real estate
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	2,395	3,471
Unpaid principal balance with related allowance recorded	2,395	3,471
Average recorded investment with related allowance recorded	2,989	3,591
Interest income recognized with related allowance recorded	110	127
Recorded investment without related allowance recorded	989	1,291
Unpaid principal balance without related allowance recorded	1,116	1,415
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	1,258	1,524
Interest income recognized without related allowance recorded	21	34
Related allowance, total impaired loans	364	586
Commercial real estate
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	128	131
Unpaid principal balance with related allowance recorded	128	131
Average recorded investment with related allowance recorded	130	1,969
Interest income recognized with related allowance recorded	11	11
Recorded investment without related allowance recorded	274	799
Unpaid principal balance without related allowance recorded	433	975
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	381	2,269
Interest income recognized without related allowance recorded	13	13
Related allowance, total impaired loans	30	23
Commercial
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded		556
Unpaid principal balance with related allowance recorded		556
Average recorded investment with related allowance recorded	292	111
Recorded investment without related allowance recorded	319	230
Unpaid principal balance without related allowance recorded	685	293
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	238	1,379
Interest income recognized without related allowance recorded	7	8
Related allowance, total impaired loans	0	53
Home equity
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	318	318
Unpaid principal balance with related allowance recorded	318	318
Average recorded investment with related allowance recorded	522	250
Recorded investment without related allowance recorded	55	124
Unpaid principal balance without related allowance recorded	192	305
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	115	195
Related allowance, total impaired loans	69	162
Consumer
Financing Receivable, Impaired [Line Items]
Recorded investment without related allowance recorded		6
Unpaid principal balance without related allowance recorded		13
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	1	1
Related allowance, total impaired loans	$ 0	$ 0

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-Publisher FASB
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