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Fair Value Measurements - Fair Value Inputs, Quantitative Information (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016
Impaired loans | Minimum | Market Approach Valuation Technique |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Fair value inputs, weighted average range (as a percent) | 0.00% | 0.00%
Impaired loans | Maximum | Market Approach Valuation Technique |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Fair value inputs, weighted average range (as a percent) | 78.11% | 66.00%
Impaired loans | Weighted Average | Market Approach Valuation Technique |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Fair value inputs, weighted average range (as a percent) | 26.10% | 31.00%
Other real estate owned | Minimum | Market Approach Valuation Technique |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Fair value inputs, weighted average range (as a percent) | 8.00% | 8.00%
Other real estate owned | Maximum | Market Approach Valuation Technique |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Fair value inputs, weighted average range (as a percent) | 96.00% | 96.00%
Other real estate owned | Weighted Average | Market Approach Valuation Technique |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Fair value inputs, weighted average range (as a percent) | 11.55% | 18.00%
Long-lived assets to be disposed of by sale | Minimum | Market Approach Valuation Technique |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Fair value inputs, weighted average range (as a percent) | 0.00% | 0.00%
Long-lived assets to be disposed of by sale | Maximum | Market Approach Valuation Technique |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Fair value inputs, weighted average range (as a percent) | 0.00% | 9.00%
Long-lived assets to be disposed of by sale | Weighted Average | Market Approach Valuation Technique |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Fair value inputs, weighted average range (as a percent) | 0.00% | 6.00%
Fair Value Measured on a Non-recurring Basis |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Impaired loans | $ 22.2 | $ (25.8)
Other real estate owned | (1.6) | (1.7)
Long-lived assets to be disposed of by sale | 0.0 | (1.0)
Estimated Fair Value | Fair Value Measured on a Non-recurring Basis |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Impaired loans | 32.6 | 39.3
Other real estate owned | 1.3 | 2.1
Long-lived assets to be disposed of by sale | 0.8 | 1.3
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] |  |
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] |  |
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] |  |
Impaired loans | 32.6 | 39.3
Other real estate owned | 1.3 | 2.1
Long-lived assets to be disposed of by sale | 0.8 | 1.3
Significant Unobservable Inputs (Level 3) | Estimated Fair Value | Fair Value Measured on a Non-recurring Basis |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] |  |
Impaired loans | $ 32.6 | $ 39.3

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- Definition Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bbb) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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