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Allowance for Credit Losses and Credit Quality of Loans, Troubled Debt Restructuring - Prior Segments (Details) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2020 USD ($) Contract | Mar. 31, 2019 USD ($) Contract
Recorded investment and number of modifications for modified loans [Abstract] |  |
Number of contracts | Contract | 8 | 20
Pre-modification outstanding recorded investment | $ 735 | $ 1,235
Post-modification outstanding recorded investment | $ 779 | $ 1,252
Recorded investment and number of modifications for subsequently defaulted TDRs [Abstract] |  |
Number of contracts | Contract | 17 | 20
Recorded Investment | $ 1,190 | $ 1,015
Commercial Loans [Member] |  |
Recorded investment and number of modifications for modified loans [Abstract] |  |
Number of contracts | Contract |  | 3
Pre-modification outstanding recorded investment |  | $ 453
Post-modification outstanding recorded investment |  | $ 453
Commercial Loans [Member] | C&I [Member] |  |
Recorded investment and number of modifications for modified loans [Abstract] |  |
Number of contracts | Contract |  | 1
Pre-modification outstanding recorded investment |  | $ 65
Post-modification outstanding recorded investment |  | $ 65
Commercial Loans [Member] | Business Banking [Member] |  |
Recorded investment and number of modifications for modified loans [Abstract] |  |
Number of contracts | Contract |  | 2
Pre-modification outstanding recorded investment |  | $ 388
Post-modification outstanding recorded investment |  | $ 388
Consumer Loans [Member] |  |
Recorded investment and number of modifications for modified loans [Abstract] |  |
Number of contracts | Contract |  | 11
Pre-modification outstanding recorded investment |  | $ 394
Post-modification outstanding recorded investment |  | $ 394
Recorded investment and number of modifications for subsequently defaulted TDRs [Abstract] |  |
Number of contracts | Contract |  | 12
Recorded Investment |  | $ 617
Consumer Loans [Member] | Indirect Auto [Member] |  |
Recorded investment and number of modifications for modified loans [Abstract] |  |
Number of contracts | Contract |  | 5
Pre-modification outstanding recorded investment |  | $ 74
Post-modification outstanding recorded investment |  | $ 74
Recorded investment and number of modifications for subsequently defaulted TDRs [Abstract] |  |
Number of contracts | Contract |  | 2
Recorded Investment |  | $ 17
Consumer Loans [Member] | Direct [Member] |  |
Recorded investment and number of modifications for modified loans [Abstract] |  |
Number of contracts | Contract |  | 6
Pre-modification outstanding recorded investment |  | $ 320
Post-modification outstanding recorded investment |  | $ 320
Recorded investment and number of modifications for subsequently defaulted TDRs [Abstract] |  |
Number of contracts | Contract |  | 10
Recorded Investment |  | $ 600
Residential Real Estate [Member] |  |
Recorded investment and number of modifications for modified loans [Abstract] |  |
Number of contracts | Contract |  | 6
Pre-modification outstanding recorded investment |  | $ 388
Post-modification outstanding recorded investment |  | $ 405
Recorded investment and number of modifications for subsequently defaulted TDRs [Abstract] |  |
Number of contracts | Contract |  | 8
Recorded Investment |  | $ 398

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- Definition Number of financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524 + Details
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- Definition Amount, after troubled debt restructuring, of modified financing receivable. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524 + Details
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- Definition Amount, before troubled debt restructuring, of financing receivable to be modified. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 33 -URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524 + Details
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