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Loans and Allowance for Loan Losses - Troubled Debt Restructuring Modifications (Details) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2018 USD ($) contract | Sep. 30, 2017 USD ($) contract | Sep. 30, 2018 USD ($) contract loan | Sep. 30, 2017 USD ($) contract loan
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Number of Contracts Modified | contract | 0 | 0 |  |
Pre-Modification Outstanding Recorded Investment | $ 0 | $ 0 |  |
Post-Modification Outstanding Recorded Investment | 0 | 0 |  |
Post-Modification Outstanding Recorded Investment at Period End | $ 0 | $ 0 |  |
Number of modified TDR loans that defaulted | loan |  |  | 0 | 0
Commercial loans | Commercial and industrial |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Number of Contracts Modified | contract |  |  | 2 |
Pre-Modification Outstanding Recorded Investment |  |  | $ 254 |
Post-Modification Outstanding Recorded Investment |  |  | 245 |
Post-Modification Outstanding Recorded Investment at Period End |  |  | $ 235 |
Consumer loans | Installment and other consumer |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Number of Contracts Modified | contract |  |  |  | 1
Pre-Modification Outstanding Recorded Investment |  |  |  | $ 50
Post-Modification Outstanding Recorded Investment |  |  |  | 50
Post-Modification Outstanding Recorded Investment at Period End |  |  |  | $ 49

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- Definition Number of financing receivables that have been modified by troubled debt restructurings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -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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- Definition Post-modification amount of investment in financing receivables modified by troubled debt restructurings. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -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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