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Fair Value Measurements - Narrative (Details) - Fair Value, Nonrecurring [Member] - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans | $ 2.8 | $ 13.7
Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Related allowance | 2.8 | 3.6
Partial loan charge-off |  | 10.1
Carrying Amount | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans | 17.5 | 41.3
Assets Held-for-sale, Long Lived, Fair Value Disclosure | 5.5 | 6.4
Changes Measurement [Member] |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets Held-for-sale, Long Lived, Fair Value Disclosure | 0.2 |
Estimated Fair Value |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Assets Held-for-sale, Long Lived, Fair Value Disclosure | 5.3 | 6.2
Estimated Fair Value | Significant Unobservable Inputs (Level 3) |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Impaired loans | $ 14.7 | $ 27.6

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