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Fair Value Measurements - Fair Value Inputs, Quantitative Information (Details) $ in Millions | 3 Months Ended | 6 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Jun. 30, 2024 USD ($) | Jun. 30, 2023 USD ($) | Jun. 30, 2024 USD ($) | Jun. 30, 2023 USD ($) | Mar. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Mar. 31, 2023 USD ($) | Dec. 31, 2022 USD ($)
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |
Real Estate Acquired Through Foreclosure | $ 6.7 | $ 14.4 | $ 6.7 | $ 14.4 | $ 14.4 | $ 16.5 | $ 13.4 | $ 12.7
Material write downs | 2.1 | $ 0.7 | 4.2 | $ 0.8 |  |  |  |
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) |  |  |  |  |  |  |  |
Collateral-dependent loans | 103.9 |  | 103.9 |  |  | 52.6 |  |
Collateral-dependent loans | Estimated Fair Value | Fair Value Measured on a Non-recurring Basis |  |  |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |
Collateral-dependent loans | 103.9 |  | 103.9 |  |  | 52.6 |  |
Collateral-dependent loans | 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) |  |  |  |  |  |  |  |
Collateral-dependent loans | 0.0 |  | 0.0 |  |  | 0.0 |  |
Collateral-dependent loans | 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) |  |  |  |  |  |  |  |
Collateral-dependent loans | 0.0 |  | 0.0 |  |  | 0.0 |  |
Collateral-dependent loans | 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) |  |  |  |  |  |  |  |
Collateral-dependent loans | $ 103.9 |  | $ 103.9 |  |  | 52.6 |  |
Collateral-dependent loans | Discount Rate | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis | Minimum | Market Approach Valuation Technique |  |  |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |
Discount rate | 0 |  | 0 |  |  |  |  |
Collateral-dependent loans | Discount Rate | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis | Maximum | Market Approach Valuation Technique |  |  |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |
Discount rate | 0.85 |  | 0.85 |  |  |  |  |
Collateral-dependent loans | Discount Rate | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis | Weighted Average | Market Approach Valuation Technique |  |  |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |
Discount rate | (0.41) |  | (0.41) |  |  |  |  |
Other real estate owned | Estimated Fair Value | Fair Value Measured on a Non-recurring Basis |  |  |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |
Other real estate owned | $ 6.7 |  | $ 6.7 |  |  | 16.5 |  |
Other real estate owned | 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) |  |  |  |  |  |  |  |
Other real estate owned | 0.0 |  | 0.0 |  |  | 0.0 |  |
Other real estate owned | 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) |  |  |  |  |  |  |  |
Other real estate owned | 0.0 |  | 0.0 |  |  | 0.0 |  |
Other real estate owned | 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) |  |  |  |  |  |  |  |
Other real estate owned | $ 6.7 |  | $ 6.7 |  |  | 16.5 |  |
Other real estate owned | Discount Rate | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis | Minimum | Market Approach Valuation Technique |  |  |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |
Discount rate | 0.19 |  | 0.19 |  |  |  |  |
Other real estate owned | Discount Rate | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis | Maximum | Market Approach Valuation Technique |  |  |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |
Discount rate | 0.90 |  | 0.90 |  |  |  |  |
Other real estate owned | Discount Rate | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis | Weighted Average | Market Approach Valuation Technique |  |  |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |
Discount rate | (0.43) |  | (0.43) |  |  |  |  |
Loans held for sale | Estimated Fair Value | Fair Value Measured on a Non-recurring Basis |  |  |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |
Financing Receivable, Held-for-Sale, Nor Part of Disposal Group, after Valuation Allowance, Fair Value Disclosure | $ 19.2 |  | $ 19.2 |  |  | 46.9 |  |
Loans held for sale | 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) |  |  |  |  |  |  |  |
Financing Receivable, Held-for-Sale, Nor Part of Disposal Group, after Valuation Allowance, Fair Value Disclosure | 0.0 |  | 0.0 |  |  | 0.0 |  |
Loans held for sale | 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) |  |  |  |  |  |  |  |
Financing Receivable, Held-for-Sale, Nor Part of Disposal Group, after Valuation Allowance, Fair Value Disclosure | 0.0 |  | 0.0 |  |  | 0.0 |  |
Loans held for sale | 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) |  |  |  |  |  |  |  |
Financing Receivable, Held-for-Sale, Nor Part of Disposal Group, after Valuation Allowance, Fair Value Disclosure | $ 19.2 |  | $ 19.2 |  |  |  |  |
Loans held for sale | 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) |  |  |  |  |  |  |  |
Financing Receivable, Held-for-Sale, Nor Part of Disposal Group, after Valuation Allowance, Fair Value Disclosure |  |  |  |  |  | 46.9 |  |
Loans held for sale | Discount Rate | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis | Minimum | Market Approach Valuation Technique |  |  |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |
Discount rate | 0 |  | 0 |  |  |  |  |
Loans held for sale | Discount Rate | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis | Maximum | Market Approach Valuation Technique |  |  |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |
Discount rate | 0.28 |  | 0.28 |  |  |  |  |
Loans held for sale | Discount Rate | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis | Weighted Average | Market Approach Valuation Technique |  |  |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |
Discount rate | (0.24) |  | (0.24) |  |  |  |  |
Long-lived assets to be disposed of by sale | 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 of by sale | $ 1.0 |  | $ 1.0 |  |  | 1.0 |  |
Long-lived assets to be disposed of by sale | 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) |  |  |  |  |  |  |  |
Long-lived assets to be disposed of by sale | 0.0 |  | 0.0 |  |  | 0.0 |  |
Long-lived assets to be disposed of by sale | 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) |  |  |  |  |  |  |  |
Long-lived assets to be disposed of by sale | 0.0 |  | 0.0 |  |  | 0.0 |  |
Long-lived assets to be disposed of by sale | 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) |  |  |  |  |  |  |  |
Long-lived assets to be disposed of by sale | $ 1.0 |  | $ 1.0 |  |  | $ 1.0 |  |
Long-lived assets to be disposed of by sale | Discount Rate | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis | Minimum | Market Approach Valuation Technique |  |  |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |
Discount rate | 0 |  | 0 |  |  |  |  |
Long-lived assets to be disposed of by sale | Discount Rate | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis | Maximum | Market Approach Valuation Technique |  |  |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |
Discount rate | 0 |  | 0 |  |  |  |  |
Long-lived assets to be disposed of by sale | Discount Rate | Significant Unobservable Inputs (Level 3) | Fair Value Measured on a Non-recurring Basis | Weighted Average | Market Approach Valuation Technique |  |  |  |  |  |  |  |
Fair Value Inputs, Assets, Quantitative Information [Line Items] (Deprecated 2018-01-31) |  |  |  |  |  |  |  |
Discount rate | 0 |  | 0 |  |  |  |  |

X
- Definition Financing Receivable, Held-for-Sale, Nor Part of Disposal Group, after Valuation Allowance, Fair Value Disclosure + References No definition available. + Details
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- Definition Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481990/310-10-45-3 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481962/310-10-50-11 + Details
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