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, 2015	Dec. 31, 2014	Dec. 31, 2013
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	$ 9,362	$ 14,186	$ 22,236
Unpaid principal balance with related allowance recorded	9,395	14,186	22,236
Average recorded investment with related allowance recorded	13,778	18,804	20,222
Interest income recognized with related allowance recorded	114	133	148
Recorded investment without related allowance recorded	13,820	6,993	5,711
Unpaid principal balance without related allowance recorded	15,985	8,330	8,015
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	4,984	6,337	7,397
Interest income recognized without related allowance recorded	90	83	91
Recorded investment, total impaired loans	23,182	21,179	27,947
Unpaid principal balance, total impaired loans	25,380	22,516	30,251
Related allowance, total impaired loans	1,946	2,239	2,981
Average recorded investment, total impaired loans	18,762	25,141	27,619
Interest income recognized, total impaired loans	204	216	239
Residential real estate loans
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	5,223	7,713	11,902
Unpaid principal balance with related allowance recorded	5,223	7,713	11,902
Average recorded investment with related allowance recorded	7,888	9,524	10,411
Interest income recognized with related allowance recorded	112	125	118
Recorded investment without related allowance recorded	5,344	1,943	2,533
Unpaid principal balance without related allowance recorded	6,245	2,604	3,846
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	1,483	2,257	2,925
Interest income recognized without related allowance recorded	8	13	28
Related allowance, total impaired loans	818	1,220	1,750
Commercial real estate loans
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	2,680	3,419	6,805
Unpaid principal balance with related allowance recorded	2,713	3,419	6,805
Average recorded investment with related allowance recorded	2,424	4,911	5,517
Interest income recognized with related allowance recorded			20
Recorded investment without related allowance recorded	3,064	4,239	2,059
Unpaid principal balance without related allowance recorded	3,663	4,502	2,782
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	2,544	2,869	3,362
Interest income recognized without related allowance recorded	65	59	55
Related allowance, total impaired loans	710	251	526
Commercial loans
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	690	1,390	1,876
Unpaid principal balance with related allowance recorded	690	1,390	1,876
Average recorded investment with related allowance recorded	1,949	2,466	2,543
Interest income recognized with related allowance recorded	2	8	10
Recorded investment without related allowance recorded	4,130	463	759
Unpaid principal balance without related allowance recorded	4,336	606	871
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	587	791	765
Interest income recognized without related allowance recorded	17	11	8
Related allowance, total impaired loans	166	168	132
Home equity loans
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	743	1,410	1,228
Unpaid principal balance with related allowance recorded	743	1,410	1,228
Average recorded investment with related allowance recorded	1,305	1,545	1,291
Recorded investment without related allowance recorded	1,190	331	343
Unpaid principal balance without related allowance recorded	1,573	581	479
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	350	399	334
Related allowance, total impaired loans	245	496	433
Consumer loans
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	26	254	425
Unpaid principal balance with related allowance recorded	26	254	425
Average recorded investment with related allowance recorded	212	358	460
Recorded investment without related allowance recorded	92	17	17
Unpaid principal balance without related allowance recorded	168	37	37
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	20	21	11
Related allowance, total impaired loans	7	$ 104	$ 140
HPFC Portfolio Segment [Member]
Financing Receivable, Impaired [Line Items]
Impaired Financing Receivable With No Related Allowance Related Allowance	0
Related allowance, total impaired loans	$ 0

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5258-111524

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