Allowance for Loan Losses and Credit Quality of Loans, Troubled Debt Restructurings (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015 USD ($) Contract	Sep. 30, 2014 USD ($) Contract	Sep. 30, 2015 USD ($) Contract	Sep. 30, 2014 USD ($) Contract
Financing Receivable, Modifications [Line Items]
Period of sustained repayment performance for nonperforming TDRs to be returned to performing status			6 months
Number of contracts \| Contract	28	11	77	70
Pre-modification outstanding recorded investment	$ 2,156	$ 429	$ 7,857	$ 5,783
Post-modification outstanding recorded investment	$ 1,993	$ 348	$ 6,230	$ 4,540
Number of TDR loans with subsequent default \| Contract	2	2	6	7
Outstanding recorded investment on TDR loans with subsequent default	$ 174	$ 73	$ 518	$ 515
Commercial Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts \| Contract			2
Pre-modification outstanding recorded investment			$ 1,470
Post-modification outstanding recorded investment			$ 359
Commercial Loans [Member] \| Commercial [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts \| Contract			1
Pre-modification outstanding recorded investment			$ 1,250
Post-modification outstanding recorded investment			$ 186
Commercial Loans [Member] \| Small Business [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts \| Contract			1	2
Pre-modification outstanding recorded investment			$ 220	$ 570
Post-modification outstanding recorded investment			$ 173	$ 558
Consumer Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts \| Contract		8	43	49
Pre-modification outstanding recorded investment		$ 250	$ 3,321	$ 3,056
Post-modification outstanding recorded investment		$ 187	$ 3,017	$ 2,354
Number of TDR loans with subsequent default \| Contract	0	1	4	7
Outstanding recorded investment on TDR loans with subsequent default	$ 0	$ 25	$ 344	$ 515
Consumer Loans [Member] \| Indirect [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts \| Contract				2
Pre-modification outstanding recorded investment				$ 69
Post-modification outstanding recorded investment				$ 38
Consumer Loans [Member] \| Home Equity [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts \| Contract	12	1	39	7
Pre-modification outstanding recorded investment	$ 863	$ 25	$ 3,212	$ 286
Post-modification outstanding recorded investment	$ 802	$ 24	$ 2,915	$ 273
Number of TDR loans with subsequent default \| Contract	0	1	4	7
Outstanding recorded investment on TDR loans with subsequent default	$ 0	$ 25	$ 344	$ 515
Consumer Loans [Member] \| Direct [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts \| Contract		7	4	40
Pre-modification outstanding recorded investment		$ 225	$ 109	$ 2,701
Post-modification outstanding recorded investment		$ 163	$ 102	$ 2,043
Residential Real Estate Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts \| Contract	16	3	32	19
Pre-modification outstanding recorded investment	$ 1,293	$ 179	$ 3,066	$ 2,157
Post-modification outstanding recorded investment	$ 1,191	$ 161	$ 2,854	$ 1,628
Number of TDR loans with subsequent default \| Contract	2	1	2	0
Outstanding recorded investment on TDR loans with subsequent default	$ 174	$ 48	$ 174	$ 0

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 33

-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953676-111524

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 34

-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953682-111524

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