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Allowance for Loan Losses and Credit Quality of Loans, Troubled Debt Restructurings (Details) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2016 USD ($) Contract | Sep. 30, 2015 USD ($) Contract | Sep. 30, 2016 USD ($) Contract | Sep. 30, 2015 USD ($) 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 | 14 | 28 | 34 | 77
Pre-modification outstanding recorded investment | $ 810 | $ 2,156 | $ 2,604 | $ 7,857
Post-modification outstanding recorded investment | $ 682 | $ 1,993 | $ 2,259 | $ 6,230
Number of TDR loans with subsequent default | Contract | 3 | 2 | 4 | 6
Outstanding recorded investment on TDR loans with subsequent default | $ 242 | $ 174 | $ 417 | $ 517
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] | Business Banking [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract |  |  |  | 1
Pre-modification outstanding recorded investment |  |  |  | $ 220
Post-modification outstanding recorded investment |  |  |  | $ 173
Consumer Loans [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract | 10 | 12 | 24 | 43
Pre-modification outstanding recorded investment | $ 580 | $ 863 | $ 1,690 | $ 3,321
Post-modification outstanding recorded investment | $ 556 | $ 802 | $ 1,567 | $ 3,017
Consumer Loans [Member] | Home Equity [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract | 10 | 12 | 24 | 43
Pre-modification outstanding recorded investment | $ 580 | $ 863 | $ 1,690 | $ 3,321
Post-modification outstanding recorded investment | $ 556 | $ 802 | $ 1,567 | $ 3,017
Number of TDR loans with subsequent default | Contract | 2 | 0 | 2 | 4
Outstanding recorded investment on TDR loans with subsequent default | $ 121 | $ 0 | $ 121 | $ 343
Residential Real Estate Mortgages [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract | 4 | 16 | 10 | 32
Pre-modification outstanding recorded investment | $ 230 | $ 1,293 | $ 914 | $ 3,066
Post-modification outstanding recorded investment | $ 126 | $ 1,191 | $ 692 | $ 2,854
Number of TDR loans with subsequent default | Contract | 1 | 2 | 2 | 2
Outstanding recorded investment on TDR loans with subsequent default | $ 121 | $ 174 | $ 296 | $ 174

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- Definition Period of sustained repayment performance for nonperforming TDRs to be returned to performing status, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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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=66008989&loc=SL6953676-111524 + Details
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