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Loans and Allowance for Loan Losses - Troubled Debt Restructuring (Details) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2017 contract | Dec. 31, 2016 USD ($) contract
Financing Receivable, Modifications [Line Items] |  |
Number of Contracts | contract | 0 |
Construction and Land Development [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Contracts | contract |  | 1
Pre-Modification Outstanding Recorded Investment |  | $ 278
Post-Modification Outstanding Recorded Investment |  | $ 278
Commercial and Industrial [Member] |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Contracts | contract |  | 1
Pre-Modification Outstanding Recorded Investment |  | $ 164
Post-Modification Outstanding Recorded Investment |  | $ 164

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- Definition Post-modification amount of investment in financing receivables 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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