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Allowance for Loan Losses and Credit Quality of Loans, Troubled Debt Restructurings (Details) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 USD ($) Contract | Jun. 30, 2016 USD ($) Contract | Jun. 30, 2017 USD ($) Contract | Jun. 30, 2016 USD ($) Contract
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract | 11 | 4 | 16 | 20
Pre-modification outstanding recorded investment | $ 4,213 | $ 226 | $ 4,522 | $ 1,792
Post-modification outstanding recorded investment | $ 4,147 | $ 224 | $ 4,469 | $ 1,595
Number of TDR loans with subsequent default | Contract | 19 | 17 | 34 | 25
Outstanding recorded investment on TDR loans with subsequent default | $ 1,183 | $ 1,251 | $ 2,013 | $ 1,838
Commercial Loans [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract | 2 |  | 2 |
Pre-modification outstanding recorded investment | $ 3,637 |  | $ 3,637 |
Post-modification outstanding recorded investment | $ 3,572 |  | $ 3,572 |
Number of TDR loans with subsequent default | Contract | 1 | 1 | 2 | 1
Outstanding recorded investment on TDR loans with subsequent default | $ 329 | $ 67 | $ 474 | $ 67
Commercial Loans [Member] | Commercial [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract | 1 |  | 1 |
Pre-modification outstanding recorded investment | $ 3,300 |  | $ 3,300 |
Post-modification outstanding recorded investment | $ 3,239 |  | $ 3,239 |
Number of TDR loans with subsequent default | Contract |  |  | 1 | 0
Outstanding recorded investment on TDR loans with subsequent default |  |  | $ 145 | $ 0
Commercial Loans [Member] | Business Banking [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract | 1 |  | 1 |
Pre-modification outstanding recorded investment | $ 337 |  | $ 337 |
Post-modification outstanding recorded investment | $ 333 |  | $ 333 |
Number of TDR loans with subsequent default | Contract | 1 | 1 | 1 | 1
Outstanding recorded investment on TDR loans with subsequent default | $ 329 | $ 67 | $ 329 | $ 67
Consumer Loans [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract | 5 | 2 | 8 | 14
Pre-modification outstanding recorded investment | $ 230 | $ 74 | $ 337 | $ 1,109
Post-modification outstanding recorded investment | $ 229 | $ 73 | $ 343 | $ 1,017
Number of TDR loans with subsequent default | Contract | 14 | 10 | 24 | 14
Outstanding recorded investment on TDR loans with subsequent default | $ 603 | $ 520 | $ 1,120 | $ 898
Consumer Loans [Member] | Indirect [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract | 3 |  | 3 |
Pre-modification outstanding recorded investment | $ 32 |  | $ 32 |
Post-modification outstanding recorded investment | $ 31 |  | $ 31 |
Number of TDR loans with subsequent default | Contract | 1 | 0 | 2 | 0
Outstanding recorded investment on TDR loans with subsequent default | $ 14 | $ 0 | $ 19 | $ 0
Consumer Loans [Member] | Home Equity [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract | 1 | 2 | 4 | 14
Pre-modification outstanding recorded investment | $ 78 | $ 74 | $ 185 | $ 1,109
Post-modification outstanding recorded investment | $ 78 | $ 73 | $ 192 | $ 1,017
Number of TDR loans with subsequent default | Contract | 13 | 10 | 22 | 14
Outstanding recorded investment on TDR loans with subsequent default | $ 589 | $ 520 | $ 1,101 | $ 898
Consumer Loans [Member] | Direct [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract | 1 |  | 1 |
Pre-modification outstanding recorded investment | $ 120 |  | $ 120 |
Post-modification outstanding recorded investment | $ 120 |  | $ 120 |
Residential Real Estate Mortgages [Member] |  |  |  |
Financing Receivable, Modifications [Line Items] |  |  |  |
Number of contracts | Contract | 4 | 2 | 6 | 6
Pre-modification outstanding recorded investment | $ 346 | $ 152 | $ 548 | $ 683
Post-modification outstanding recorded investment | $ 346 | $ 151 | $ 554 | $ 578
Number of TDR loans with subsequent default | Contract | 4 | 6 | 8 | 10
Outstanding recorded investment on TDR loans with subsequent default | $ 251 | $ 664 | $ 419 | $ 873

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