Loans, Allowance for Credit Losses, and Credit Quality Troubled Debt Restructurings Subsequent Default (Details) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2015 USD ($) loan	Jun. 30, 2014 USD ($) loan	Jun. 30, 2015 USD ($) loan	Jun. 30, 2014 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	29	39	53	58
Recorded Investment	$ 1,376	$ 4,033	$ 3,571	$ 6,209
Commercial Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	1	2	1	2
Recorded Investment	$ 43	$ 135	$ 43	$ 135
Commercial Real Estate Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	0	2	1	2
Recorded Investment	$ 0	$ 612	$ 297	$ 612
Commercial Real Estate Investor [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan		1		1
Recorded Investment		$ 1,291		$ 1,291
Real Estate Construction [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan		0		1
Recorded Investment		$ 0		$ 161
Home Equity Portfolio [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	15	13	22	18
Recorded Investment	$ 341	$ 414	$ 1,001	$ 651
Installment and Credit Cards [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan		1		2
Recorded Investment		$ 16		$ 25
Residential Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	13	20	29	32
Recorded Investment	$ 992	$ 1,565	$ 2,230	$ 3,334

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

+ References

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