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Allowance for Loan Losses and Credit Quality of Loans, Troubled Debt Restructurings (Details) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2018 USD ($) Contract | Mar. 31, 2017 USD ($) Contract
Financing Receivable, Modifications [Line Items] |  |
Number of contracts | Contract | 16 | 3
Pre-modification outstanding recorded investment | $ 765 | $ 219
Post-modification outstanding recorded investment | $ 855 | $ 215
Number of contracts | Contract | 23 | 18
Recorded Investment | $ 1,574 | $ 980
Commercial Loans [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of contracts | Contract | 3 |
Pre-modification outstanding recorded investment | $ 319 |
Post-modification outstanding recorded investment | $ 410 |
Number of contracts | Contract | 1 | 1
Recorded Investment | $ 200 | $ 145
Commercial Loans [Member] | Commercial [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of contracts | Contract | 0 | 1
Recorded Investment | $ 0 | $ 145
Commercial Loans [Member] | Business Banking [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of contracts | Contract | 3 |
Pre-modification outstanding recorded investment | $ 319 |
Post-modification outstanding recorded investment | $ 410 |
Number of contracts | Contract | 1 | 0
Recorded Investment | $ 200 | $ 0
Consumer Loans [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of contracts | Contract | 8 | 2
Pre-modification outstanding recorded investment | $ 123 | $ 78
Post-modification outstanding recorded investment | $ 122 | $ 77
Number of contracts | Contract | 14 | 13
Recorded Investment | $ 870 | $ 668
Consumer Loans [Member] | Indirect [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of contracts | Contract | 0 | 1
Recorded Investment | $ 0 | $ 5
Consumer Loans [Member] | Dealer Finance [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of contracts | Contract | 6 |
Pre-modification outstanding recorded investment | $ 82 |
Post-modification outstanding recorded investment | $ 81 |
Consumer Loans [Member] | Home Equity [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of contracts | Contract |  | 2
Pre-modification outstanding recorded investment |  | $ 78
Post-modification outstanding recorded investment |  | $ 77
Number of contracts | Contract | 0 | 12
Recorded Investment | $ 0 | $ 663
Consumer Loans [Member] | Direct [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of contracts | Contract | 2 |
Pre-modification outstanding recorded investment | $ 41 |
Post-modification outstanding recorded investment | $ 41 |
Number of contracts | Contract | 14 | 0
Recorded Investment | $ 870 | $ 0
Residential Real Estate Mortgages [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of contracts | Contract | 5 | 1
Pre-modification outstanding recorded investment | $ 323 | $ 141
Post-modification outstanding recorded investment | $ 323 | $ 138
Number of contracts | Contract | 8 | 4
Recorded Investment | $ 504 | $ 167

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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=84173941&loc=SL6953676-111524 + Details
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