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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, 2017 USD ($) Contract | Sep. 30, 2016 USD ($) Contract | Sep. 30, 2017 USD ($) Contract | Sep. 30, 2016 USD ($) Contract
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract | 6 | 14 | 23 | 34
Pre-modification outstanding recorded investment | $ 714 | $ 810 | $ 5,235 | $ 2,604
Post-modification outstanding recorded investment | $ 747 | $ 682 | $ 5,211 | $ 2,259
Number of TDR loans with subsequent default | Contract | 19 | 26 | 46 | 47
Outstanding recorded investment on TDR loans with subsequent default | $ 1,181 | $ 1,501 | $ 2,691 | $ 2,945
Commercial Loans [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract |  |  | 2 |
Pre-modification outstanding recorded investment |  |  | $ 3,637 |
Post-modification outstanding recorded investment |  |  | $ 3,572 |
Number of TDR loans with subsequent default | Contract | 0 | 1 | 2 | 2
Outstanding recorded investment on TDR loans with subsequent default | $ 0 | $ 169 | $ 474 | $ 236
Commercial Loans [Member] | Commercial [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract |  |  | 1 |
Pre-modification outstanding recorded investment |  |  | $ 3,300 |
Post-modification outstanding recorded investment |  |  | $ 3,239 |
Number of TDR loans with subsequent default | Contract | 0 | 1 | 1 | 1
Outstanding recorded investment on TDR loans with subsequent default | $ 0 | $ 169 | $ 145 | $ 169
Commercial Loans [Member] | Business Banking [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract |  |  | 1 |
Pre-modification outstanding recorded investment |  |  | $ 337 |
Post-modification outstanding recorded investment |  |  | $ 333 |
Number of TDR loans with subsequent default | Contract |  |  | 1 | 1
Outstanding recorded investment on TDR loans with subsequent default |  |  | $ 329 | $ 67
Consumer Loans [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract | 5 | 10 | 13 | 24
Pre-modification outstanding recorded investment | $ 196 | $ 580 | $ 532 | $ 1,690
Post-modification outstanding recorded investment | $ 229 | $ 556 | $ 571 | $ 1,567
Number of TDR loans with subsequent default | Contract | 13 | 17 | 32 | 30
Outstanding recorded investment on TDR loans with subsequent default | $ 635 | $ 847 | $ 1,400 | $ 1,634
Consumer Loans [Member] | Indirect [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract | 1 |  | 4 |
Pre-modification outstanding recorded investment | $ 7 |  | $ 39 |
Post-modification outstanding recorded investment | $ 7 |  | $ 37 |
Number of TDR loans with subsequent default | Contract | 1 | 0 | 2 | 0
Outstanding recorded investment on TDR loans with subsequent default | $ 13 | $ 0 | $ 19 | $ 0
Consumer Loans [Member] | Home Equity [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract | 4 | 10 | 8 | 24
Pre-modification outstanding recorded investment | $ 189 | $ 580 | $ 373 | $ 1,690
Post-modification outstanding recorded investment | $ 222 | $ 556 | $ 414 | $ 1,567
Number of TDR loans with subsequent default | Contract | 12 | 17 | 30 | 30
Outstanding recorded investment on TDR loans with subsequent default | $ 622 | $ 847 | $ 1,381 | $ 1,634
Consumer Loans [Member] | Direct [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract |  |  | 1 |
Pre-modification outstanding recorded investment |  |  | $ 120 |
Post-modification outstanding recorded investment |  |  | $ 120 |
Residential Real Estate Mortgages [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract | 1 | 4 | 8 | 10
Pre-modification outstanding recorded investment | $ 518 | $ 230 | $ 1,066 | $ 914
Post-modification outstanding recorded investment | $ 518 | $ 126 | $ 1,068 | $ 692
Number of TDR loans with subsequent default | Contract | 6 | 8 | 12 | 15
Outstanding recorded investment on TDR loans with subsequent default | $ 546 | $ 485 | $ 817 | $ 1,075

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