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Loans and Allowance for Loan Losses - Troubled Debt Restructuring Modifications (Details) | 12 Months Ended
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Dec. 31, 2018 USD ($) contract | Dec. 31, 2017 USD ($) contract
Financing Receivable, Modifications [Line Items] |  |
Total of TDR loans charged-off within previous 12 months | $ 0 | $ 0
Consumer loans | Installment and other consumer |  |
Financing Receivable, Modifications [Line Items] |  |
Number of Contracts Modified | contract | 2 | 1
Pre-Modification Outstanding Recorded Investment | $ 254,000 | $ 50,000
Post-Modification Outstanding Recorded Investment | 245,000 | 50,000
Post-Modification Outstanding Recorded Investment at Period End | $ 172,000 | $ 47,000

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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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