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Loans and Credit Quality - Summary of Trouble Debt Restructurings that Subsequently Defaulted (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2018 USD ($) contract | Dec. 31, 2017 contract | Dec. 31, 2016 contract
Financing Receivable, Modifications [Line Items] |  |  |
Number of Contracts | contract | 6 | 0 | 0
Recorded Investment | $ | $ 2,860 |  |
Asset Quality Rating - Substandard | Commercial |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Contracts | contract | 4 |  |
Recorded Investment | $ | $ 1,166 |  |
Asset Quality Rating - Substandard | Real estate term owner occupied |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of Contracts | contract | 2 |  |
Recorded Investment | $ | $ 1,694 |  |

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- Definition Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 34 -URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524 + Details
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