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v3.19.1

Fair Value Measurements - Fair Value Inputs, Quantitative Information (Details) - USD ($) | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Mar. 31, 2018 | Dec. 31, 2018 | Mar. 31, 2019 | Dec. 31, 2017
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |
Write downs on OREO properties | $ 0 |  |  |
Minimum | Market Approach Valuation Technique |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |
Discount Rate for Level 3 Fair Value Disclosure |  | 0.00% |  |
Maximum | Market Approach Valuation Technique |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |
Discount Rate for Assets HFS Level 3 Fair Value |  | 43.00% |  |
Discount Rate for OREO Level 3 Fair Value |  | 96.00% |  |
Weighted Average | Market Approach Valuation Technique |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |
Discount Rate for Assets HFS Level 3 Fair Value |  | 10.00% |  |
Discount Rate for OREO Level 3 Fair Value |  | 39.00% |  |
Discount Rate for Level 3 Fair Value Disclosure |  | 13.00% |  |
Carrying Amount |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |
Net loans held for investment |  | $ 8,397,400,000 | $ 8,386,800,000 |
Change During Period | Fair Value Measured on a Non-recurring Basis |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |
Fair Value of long-lived assets to be disposed of by sale |  | 500,000 |  | $ 500,000
Estimated Fair Value |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |
Net loans held for investment |  | 8,439,700,000 | 8,408,600,000 |
Estimated Fair Value | Fair Value Measured on a Non-recurring Basis |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |
Fair Value of long-lived assets to be disposed of by sale |  | 5,500,000 |  | 4,900,000
Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |
Partial loan charge-offs |  | 6,200,000 |  | 5,400,000
Long-lived assets to be disposed, fair value disclosure |  | 4,900,000 | 5,500,000 |
Impaired loans |  | 24,100,000 |  |
Other real estate owned |  | 600,000 | 2,000,000 |
Significant Unobservable Inputs (Level 3) | Carrying Amount | Fair Value Measured on a Non-recurring Basis |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |
Impaired loans |  | 44,200,000 |  | 36,300,000
Fair Value of long-lived assets to be disposed of by sale |  | 6,000,000 |  | 5,400,000
Significant Unobservable Inputs (Level 3) | Estimated Fair Value |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |
Net loans held for investment |  | 24,100,000 | 30,900,000 |
Significant Unobservable Inputs (Level 3) | Estimated Fair Value | Fair Value Measured on a Non-recurring Basis |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |
Long-lived assets to be disposed, fair value disclosure |  | 4,900,000 | 5,500,000 |
Impaired loans |  | $ 30,900,000 | 30,900,000 | $ 24,100,000
Other real estate owned |  |  | $ 2,000,000 |
Measurement Input, Discount Rate [Member] | Minimum | Market Approach Valuation Technique |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |
Discount Rate for Assets HFS Level 3 Fair Value |  | 0.00% |  |
Discount Rate for OREO Level 3 Fair Value |  | 8.00% |  |
Measurement Input, Discount Rate [Member] | Maximum | Market Approach Valuation Technique |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |
Discount Rate for Level 3 Fair Value Disclosure |  | 26.00% |  |

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- Definition Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -URI http://asc.fasb.org/subtopic&trid=2196772 + Details
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