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Fair Value of Financial Instruments - Assets and Liabilities Measured at Fair Value Using Significant Unobservable Inputs (Level 3) (Details) $ in Thousands | Sep. 30, 2019 USD ($) | Dec. 31, 2018 USD ($) | Sep. 30, 2018 USD ($) | Dec. 31, 2017 USD ($)
--- | --- | --- | --- | ---
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |
OREO | $ 1,248 | $ 1,505 | $ 1,489 | $ 3,792
Fair Value, Inputs, Level 3 [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |
Impaired loans | 3,661 |  |  |
OREO | 1,248 |  |  |
Assets held-for-sale | $ 198 |  |  |
Fair Value, Inputs, Level 3 [Member] | Minimum [Member] | Measurement Input, Comparability Adjustment [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |
Impaired loans | 0.09 |  |  |
OREO | 0.09 |  |  |
Assets held-for-sale | 0.09 |  |  |
Fair Value, Inputs, Level 3 [Member] | Maximum [Member] | Measurement Input, Comparability Adjustment [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |
Impaired loans | 0.10 |  |  |
OREO | 0.10 |  |  |
Assets held-for-sale | 0.10 |  |  |
Fair Value, Inputs, Level 3 [Member] | Weighted Average [Member] | Measurement Input, Comparability Adjustment [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items] |  |  |  |
Impaired loans | (0.095) |  |  |
OREO | (0.095) |  |  |
Assets held-for-sale | (0.095) |  |  |

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