Allowance for Loan Losses and Credit Quality of Loans, Troubled Debt Restructurings (Details) (USD $)	3 Months Ended
Mar. 31, 2015 Contract	Mar. 31, 2014 Contract
Financing Receivable, Modifications [Line Items]
Period of sustained repayment performance for nonperforming TDRs to be returned to performing status	6 months
Home Equity [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts	5	22
Pre-modification outstanding recorded investment	$ 0.1	$ 1,100,000
Number of TDR loans with subsequent default	1	1
Outstanding recorded investment on TDR loans with subsequent default	8,000	11,000
Direct [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts	15
Pre-modification outstanding recorded investment	1,200,000
Number of TDR loans with subsequent default	4
Outstanding recorded investment on TDR loans with subsequent default	200,000
Residential Real Estate Mortgages [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts	9	12
Pre-modification outstanding recorded investment	800,000	1,000,000
Number of TDR loans with subsequent default		1
Outstanding recorded investment on TDR loans with subsequent default		$ 100,000

Period of sustained repayment performance for nonperforming TDRs to be returned to performing status.

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- Definition

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=35738203&loc=SL6953676-111524

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Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

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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=35738203&loc=SL6953682-111524

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Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

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