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Basis of Presentation and Significant Accounting Policies - Contributions and Plan Assets (Details) - Pension Plan - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
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Defined Benefit Plan Disclosure [Line Items] |  |
Projected benefit obligation | $ 16.2 | $ 17.2
Qualified Plan | 401(k) plan assets |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan assets | 245.7 | 207.1
Nonqualified Plan |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan assets | $ 13.9 | $ 13.6

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