Loans, Allowance for Credit Losses, and Credit Quality Troubled Debt Restructurings Subsequent Default (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015 USD ($) loan	Sep. 30, 2014 USD ($) loan	Sep. 30, 2015 USD ($) loan	Sep. 30, 2014 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	33	32	68	84
Recorded Investment	$ 2,432	$ 2,372	$ 5,253	$ 7,744
Commercial and Industrial [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	1	0	1	1
Recorded Investment	$ 153	$ 0	$ 153	$ 52
Commercial Real Estate Owner Occupied [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	0	0	1	2
Recorded Investment	$ 0	$ 0	$ 297	$ 203
Commercial Real Estate Investor [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan		1		2
Recorded Investment		$ 493		$ 1,613
Real Estate Construction [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan		0		1
Recorded Investment		$ 0		$ 160
Home Equity Portfolio [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	14	11	21	20
Recorded Investment	$ 421	$ 312	$ 627	$ 598
Installment and Credit Cards [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan		1		3
Recorded Investment		$ 10		$ 34
Residential Portfolio Segment [Member]
Financing Receivable, Modifications [Line Items]
Number of Loans \| loan	18	19	45	55
Recorded Investment	$ 1,858	$ 1,557	$ 4,176	$ 5,084

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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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