Loans and Allowance for Loan Losses (Summary of Impaired Loan Balances and Associated Allowance by Portfolio Segment) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	$ 14,186	$ 22,236	$ 19,781
Unpaid principal balance with related allowance recorded	14,186	22,236	19,781
Average recorded investment with related allowance recorded	18,804	20,222	21,591
Interest income recognized with related allowance recorded	133	148	114
Recorded investment without related allowance recorded	6,993	5,711	7,376
Unpaid principal balance without related allowance recorded	8,330	8,015	9,476
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	6,337	7,397	5,616
Interest income recognized without related allowance recorded	83	91	72
Recorded investment, total impaired loans	21,179	27,947	27,157
Unpaid principal balance, total impaired loans	22,516	30,251	29,257
Related allowance, total impaired loans	2,239	2,981	3,106
Average recorded investment, total impaired loans	25,141	27,619	27,207
Interest income recognized, total impaired loans	216	239	186
Residential real estate loans
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	7,713	11,902	11,021
Unpaid principal balance with related allowance recorded	7,713	11,902	11,021
Average recorded investment with related allowance recorded	9,524	10,411	10,585
Interest income recognized with related allowance recorded	125	118	114
Recorded investment without related allowance recorded	1,943	2,533	2,784
Unpaid principal balance without related allowance recorded	2,604	3,846	3,841
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	2,257	2,925	2,548
Interest income recognized without related allowance recorded	13	28	26
Related allowance, total impaired loans	1,220	1,750	2,255
Commercial real estate loans
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	3,419	6,805	4,296
Unpaid principal balance with related allowance recorded	3,419	6,805	4,296
Average recorded investment with related allowance recorded	4,911	5,517	5,551
Interest income recognized with related allowance recorded		20
Recorded investment without related allowance recorded	4,239	2,059	3,672
Unpaid principal balance without related allowance recorded	4,502	2,782	4,127
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	2,869	3,362	2,056
Interest income recognized without related allowance recorded	59	55	33
Related allowance, total impaired loans	251	526	265
Commercial loans
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	1,390	1,876	2,971
Unpaid principal balance with related allowance recorded	1,390	1,876	2,971
Average recorded investment with related allowance recorded	2,466	2,543	3,927
Interest income recognized with related allowance recorded	8	10
Recorded investment without related allowance recorded	463	759	639
Unpaid principal balance without related allowance recorded	606	871	956
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	791	765	389
Interest income recognized without related allowance recorded	11	8	13
Related allowance, total impaired loans	168	132	286
Home equity loans
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	1,410	1,228	1,236
Unpaid principal balance with related allowance recorded	1,410	1,228	1,236
Average recorded investment with related allowance recorded	1,545	1,291	1,289
Recorded investment without related allowance recorded	331	343	279
Unpaid principal balance without related allowance recorded	581	479	550
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	399	334	617
Related allowance, total impaired loans	496	433	261
Consumer loans
Financing Receivable, Impaired [Line Items]
Recorded investment with related allowance recorded	254	425	257
Unpaid principal balance with related allowance recorded	254	425	257
Average recorded investment with related allowance recorded	358	460	239
Recorded investment without related allowance recorded	17	17	2
Unpaid principal balance without related allowance recorded	37	37	2
Impaired Financing Receivable With No Related Allowance Related Allowance	0	0
Average recorded investment without related allowance recorded	21	11	6
Related allowance, total impaired loans	$ 104	$ 140	$ 39

Impaired Financing Receivable, With No Related Allowance, Related Allowance

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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://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-Subparagraph (c)(1)

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-Publisher FASB

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-Topic 310

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