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Fair Value Measurements - Fair Value Inputs, Quantitative Information (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
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%) | (0.00%)
Maximum | Market Approach Valuation Technique |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
Discount Rate for OREO Level 3 Fair Value | (96.00%) | (96.00%)
Discount Rate for Assets HFS Level 3 Fair Value | 43.00% | 0.00%
Weighted Average | Market Approach Valuation Technique |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
Discount Rate for Level 3 Fair Value Disclosure | (13.00%) | (26.00%)
Discount Rate for OREO Level 3 Fair Value | (39.00%) | (12.00%)
Discount Rate for Assets HFS Level 3 Fair Value | 10.00% | 0.00%
Fair Value Measured on a Non-recurring Basis |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
Impaired loans | $ (12.2) | $ (22.2)
Other real estate owned | (0.6) | (1.6)
Long-lived assets to be disposed of by sale | (0.5) | 0.0
Estimated Fair Value | Fair Value Measured on a Non-recurring Basis |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
Impaired loans | 24.1 |
Other real estate owned | 0.6 |
Long-lived assets to be disposed of by sale | 4.9 |
Quoted Prices in Active Markets for Identical Assets (Level 1) | Fair Value Measured on a Non-recurring Basis |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
Impaired loans | 0.0 | 0.0
Other real estate owned | 0.0 | 0.0
Long-lived assets to be disposed of by sale | 0.0 | 0.0
Significant Other Observable Inputs (Level 2) | Fair Value Measured on a Non-recurring Basis |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |
Impaired loans | 0.0 | 0.0
Other real estate owned | 0.0 | 0.0
Long-lived assets to be disposed of by sale | 0.0 | 0.0
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) |  |
Impaired loans | 24.1 | 32.6
Other real estate owned | 0.6 | 1.3
Long-lived assets to be disposed of by sale | 4.9 | 0.8
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) |  |
Impaired loans | $ 24.1 | $ 32.6
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 OREO Level 3 Fair Value | (8.00%) | (8.00%)
Discount Rate for Assets HFS Level 3 Fair Value | 0.00% | 0.00%
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%) | (78.00%)

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- Definition Discount Rate for Impaired Loans Level 3 Fair Value + References No definition available. + Details
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