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Allowance for Loan Losses and Credit Quality of Loans, Troubled Debt Restructured Loans (Details) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 USD ($) Contract | Jun. 30, 2017 USD ($) Contract | Jun. 30, 2018 USD ($) Contract | Jun. 30, 2017 USD ($) Contract
Troubled Debt Restructured Loans [Abstract] |  |  |  |
Number of contracts | Contract | 2 | 11 | 17 | 16
Pre-modification outstanding recorded investment | $ 19 | $ 4,213 | $ 828 | $ 4,522
Post-modification outstanding recorded investment | $ 18 | $ 4,147 | $ 829 | $ 4,469
Number of contracts | Contract | 21 | 19 | 40 | 34
Recorded Investment | $ 1,152 | $ 1,183 | $ 2,425 | $ 2,013
Commercial Loans [Member] |  |  |  |
Troubled Debt Restructured Loans [Abstract] |  |  |  |
Number of contracts | Contract | 1 | 2 | 3 | 2
Pre-modification outstanding recorded investment | $ 6 | $ 3,637 | $ 369 | $ 3,637
Post-modification outstanding recorded investment | $ 5 | $ 3,572 | $ 371 | $ 3,572
Number of contracts | Contract | 1 | 1 | 2 | 2
Recorded Investment | $ 58 | $ 329 | $ 258 | $ 474
Commercial Loans [Member] | Commercial [Member] |  |  |  |
Troubled Debt Restructured Loans [Abstract] |  |  |  |
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 contracts | Contract | 0 |  | 0 | 1
Recorded Investment | $ 0 |  | $ 0 | $ 145
Commercial Loans [Member] | Business Banking [Member] |  |  |  |
Troubled Debt Restructured Loans [Abstract] |  |  |  |
Number of contracts | Contract | 1 | 1 | 3 | 1
Pre-modification outstanding recorded investment | $ 6 | $ 337 | $ 369 | $ 337
Post-modification outstanding recorded investment | $ 5 | $ 333 | $ 371 | $ 333
Number of contracts | Contract | 1 | 1 | 2 | 1
Recorded Investment | $ 58 | $ 329 | $ 258 | $ 329
Consumer Loans [Member] |  |  |  |
Troubled Debt Restructured Loans [Abstract] |  |  |  |
Number of contracts | Contract | 1 | 5 | 9 | 8
Pre-modification outstanding recorded investment | $ 13 | $ 230 | $ 136 | $ 337
Post-modification outstanding recorded investment | $ 13 | $ 229 | $ 135 | $ 343
Number of contracts | Contract | 13 | 14 | 25 | 24
Recorded Investment | $ 495 | $ 603 | $ 1,260 | $ 1,120
Consumer Loans [Member] | Indirect [Member] |  |  |  |
Troubled Debt Restructured Loans [Abstract] |  |  |  |
Number of contracts | Contract |  | 3 |  | 3
Pre-modification outstanding recorded investment |  | $ 32 |  | $ 32
Post-modification outstanding recorded investment |  | $ 31 |  | $ 31
Number of contracts | Contract | 0 | 1 | 0 | 2
Recorded Investment | $ 0 | $ 14 | $ 0 | $ 19
Consumer Loans [Member] | Dealer Finance [Member] |  |  |  |
Troubled Debt Restructured Loans [Abstract] |  |  |  |
Number of contracts | Contract | 1 |  | 7 |
Pre-modification outstanding recorded investment | $ 13 |  | $ 95 |
Post-modification outstanding recorded investment | $ 13 |  | $ 94 |
Consumer Loans [Member] | Home Equity [Member] |  |  |  |
Troubled Debt Restructured Loans [Abstract] |  |  |  |
Number of contracts | Contract |  | 1 |  | 4
Pre-modification outstanding recorded investment |  | $ 78 |  | $ 185
Post-modification outstanding recorded investment |  | $ 78 |  | $ 192
Number of contracts | Contract | 0 | 13 | 0 | 22
Recorded Investment | $ 0 | $ 589 | $ 0 | $ 1,101
Consumer Loans [Member] | Direct [Member] |  |  |  |
Troubled Debt Restructured Loans [Abstract] |  |  |  |
Number of contracts | Contract |  | 1 | 2 | 1
Pre-modification outstanding recorded investment |  | $ 120 | $ 41 | $ 120
Post-modification outstanding recorded investment |  | $ 120 | $ 41 | $ 120
Number of contracts | Contract | 13 | 0 | 25 | 0
Recorded Investment | $ 495 | $ 0 | $ 1,260 | $ 0
Residential Real Estate [Member] |  |  |  |
Troubled Debt Restructured Loans [Abstract] |  |  |  |
Number of contracts | Contract |  | 4 | 5 | 6
Pre-modification outstanding recorded investment |  | $ 346 | $ 323 | $ 548
Post-modification outstanding recorded investment |  | $ 346 | $ 323 | $ 554
Number of contracts | Contract | 7 | 4 | 13 | 8
Recorded Investment | $ 599 | $ 251 | $ 907 | $ 419

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