Loans and Allowance for Loan Losses (Summary of Impaired Loan Balances and Associated Allowance by Portfolio Segment) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	$ 2,841	$ 4,476	$ 9,280
Unpaid principal balance with related allowance recorded	2,841	4,476	9,280
Average recorded investment with related allowance recorded	3,933	5,921	12,257
Interest income recognized with related allowance recorded	121	138	153
Recorded investment without related allowance recorded	1,637	2,450	4,310
Unpaid principal balance without related allowance recorded	2,426	3,001	6,216
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	1,993	5,368	4,709
Interest income recognized without related allowance recorded	41	55	62
Recorded investment, total impaired loans	4,478	6,926	13,590
Unpaid principal balance, total impaired loans	5,267	7,477	15,496
Related allowance, total impaired loans	463	824	2,009
Average recorded investment, total impaired loans	5,926	11,289	16,966
Interest income recognized, total impaired loans	162	193	215
Residential real estate
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	2,395	3,471	3,858
Unpaid principal balance with related allowance recorded	2,395	3,471	3,858
Average recorded investment with related allowance recorded	2,989	3,591	3,177
Interest income recognized with related allowance recorded	110	127	131
Recorded investment without related allowance recorded	989	1,291	1,313
Unpaid principal balance without related allowance recorded	1,116	1,415	1,673
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	1,258	1,524	1,345
Interest income recognized without related allowance recorded	21	34	15
Related allowance, total impaired loans	364	586	568
Commercial real estate
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	128	131	5,422
Unpaid principal balance with related allowance recorded	128	131	5,422
Average recorded investment with related allowance recorded	130	1,969	8,900
Interest income recognized with related allowance recorded	11	11	22
Recorded investment without related allowance recorded	274	799	777
Unpaid principal balance without related allowance recorded	433	975	1,084
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	381	2,269	1,132
Interest income recognized without related allowance recorded	13	13	29
Related allowance, total impaired loans	30	23	1,441
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	31
Recorded investment without related allowance recorded	319	230	1,791
Unpaid principal balance without related allowance recorded	685	293	2,964
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	238	1,379	1,920
Interest income recognized without related allowance recorded	7	8	10
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	125
Recorded investment without related allowance recorded	55	124	429
Unpaid principal balance without related allowance recorded	192	305	495
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	115	195	310
Interest income recognized without related allowance recorded			8
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	2
Related allowance, total impaired loans	0	0
HPFC Portfolio Segment
Financing Receivable, Impaired [Line Items]
Average recorded investment with related allowance recorded			24
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded
Related allowance, total impaired loans	$ 0	$ 0

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