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Fair Value Measurements (Details 2) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Fair Value, Instruments Classified in Shareholders' Equity Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |
Debt Securities, Available-for-sale |  | $ 437,689 | $ 442,752
Discounted cash flow methodology [Member] | Significant Unobservable Inputs (Level 3) | Weighted Average [Member] |  |  |
Investments in securities that are classified as level 3 |  |  |
Cumulative Default |  | 16.10% | 16.20%
Loss Given Default |  | 92.10% | 94.80%
Cure Given Default |  | 60.90% | 60.90%
Pooled trust preferred securities | Significant Unobservable Inputs (Level 3) |  |  |
Fair Value, Instruments Classified in Shareholders' Equity Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] |  |  |
Debt Securities, Available-for-sale |  | $ 1,314 | $ 1,329
Pooled trust preferred securities | Discounted cash flow methodology [Member] | Significant Unobservable Inputs (Level 3) | Minimum [Member] |  |  |
Investments in securities that are classified as level 3 |  |  |
Cumulative Default |  | 5.00% | 5.00%
Loss Given Default |  | 85.00% | 85.00%
Cure Given Default |  | 0.00% | 0.00%
Pooled trust preferred securities | Discounted cash flow methodology [Member] | Significant Unobservable Inputs (Level 3) | Maximum [Member] |  |  |
Investments in securities that are classified as level 3 |  |  |
Cumulative Default |  | 100.00% | 100.00%
Loss Given Default |  | 100.00% | 100.00%
Cure Given Default |  | 75.00% | 75.00%
Fair Value, Measurements, Recurring [Member] | Collateral dependent impaired loans | Significant Unobservable Inputs (Level 3) |  |  |
Investments in securities that are classified as level 3 |  |  |
Assets, Fair Value Disclosure | [1] | $ 28,261 | $ 29,109
Measurement Input, Constant Prepayment Rate [Member] | Discounted cash flow methodology [Member] | Significant Unobservable Inputs (Level 3) | Weighted Average [Member] |  |  |
Investments in securities that are classified as level 3 |  |  |
Debt Securities, Available-for-sale, Measurement Input |  | 0.025 | 0.021
Measurement Input, Constant Prepayment Rate [Member] | Pooled trust preferred securities | Discounted cash flow methodology [Member] | Significant Unobservable Inputs (Level 3) | Minimum [Member] |  |  |
Investments in securities that are classified as level 3 |  |  |
Debt Securities, Available-for-sale, Measurement Input |  | 0 | 0
Measurement Input, Constant Prepayment Rate [Member] | Pooled trust preferred securities | Discounted cash flow methodology [Member] | Significant Unobservable Inputs (Level 3) | Maximum [Member] |  |  |
Investments in securities that are classified as level 3 |  |  |
Debt Securities, Available-for-sale, Measurement Input |  | 0.58 | 0.59
[1] | Fair value is generally determined through independent appraisals of the underlying collateral, which generally include various Level 3 inputs which are not identifiable. Appraisals may be adjusted by management for qualitative factors such as economic factors and estimated liquidation expenses. The range of these possible adjustments may vary.

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