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, 2016	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	$ 14,858	$ 5,475	$ 5,931
Unpaid principal balance with related allowance recorded	14,858	5,507	5,931
Average recorded investment with related allowance recorded	9,418	9,857	18,117
Interest income recognized with related allowance recorded	106	114	133
Recorded investment without related allowance recorded	5,396	9,760	6,993
Unpaid principal balance without related allowance recorded	7,756	12,942	8,330
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	6,970	6,695	6,337
Interest income recognized without related allowance recorded	76	90	58
Recorded investment, total impaired loans	20,254	15,235	12,924
Unpaid principal balance, total impaired loans	22,614	18,449	14,261
Related allowance, total impaired loans	2,007	1,369	953
Average recorded investment, total impaired loans	16,388	16,552	24,454
Interest income recognized, total impaired loans	182	204	191
Residential real estate loans
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	3,019	3,191	4,468
Unpaid principal balance with related allowance recorded	3,019	3,191	4,468
Average recorded investment with related allowance recorded	3,088	6,064	9,254
Interest income recognized with related allowance recorded	106	112	125
Recorded investment without related allowance recorded	1,329	2,835	1,943
Unpaid principal balance without related allowance recorded	1,800	4,353	2,604
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	2,057	2,175	2,257
Interest income recognized without related allowance recorded	9	8	7
Related allowance, total impaired loans	483	544	787
Commercial real estate loans
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	11,443	1,825	1,140
Unpaid principal balance with related allowance recorded	11,443	1,857	1,140
Average recorded investment with related allowance recorded	5,165	1,753	4,721
Recorded investment without related allowance recorded	1,874	2,785	4,239
Unpaid principal balance without related allowance recorded	2,369	3,426	4,502
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	2,214	2,719	2,869
Interest income recognized without related allowance recorded	51	65	40
Related allowance, total impaired loans	1,373	644	78
Commercial loans
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded		156	183
Unpaid principal balance with related allowance recorded		156	183
Average recorded investment with related allowance recorded	762	945	2,366
Interest income recognized with related allowance recorded		2	8
Recorded investment without related allowance recorded	2,028	3,781	463
Unpaid principal balance without related allowance recorded	3,209	4,325	606
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	2,507	1,412	791
Interest income recognized without related allowance recorded	16	17	11
Related allowance, total impaired loans	0	92	10
Home equity loans
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	299	303
Unpaid principal balance with related allowance recorded	299	303
Average recorded investment with related allowance recorded	305	900	1,428
Recorded investment without related allowance recorded	158	285	331
Unpaid principal balance without related allowance recorded	368	688	581
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	180	369	399
Related allowance, total impaired loans	86	89
Consumer loans
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded			140
Unpaid principal balance with related allowance recorded			140
Average recorded investment with related allowance recorded		195	348
Recorded investment without related allowance recorded	7	74	17
Unpaid principal balance without related allowance recorded	10	150	37
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	12	20	21
Related allowance, total impaired loans	0	0	$ 78
HPFC Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	97
Unpaid principal balance with related allowance recorded	97
Average recorded investment with related allowance recorded	98
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded
Related allowance, total impaired loans	$ 65	$ 0

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