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Debt - Debt Outstanding (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023 | Mar. 10, 2022 | Feb. 15, 2022 | Sep. 22, 2020
--- | --- | --- | --- | --- | ---
Debt Instrument [Line Items] |  |  |  |  |
Long-Term Debt, Current Maturities | $ 449.9 | $ 0.0 |  |  |
Long-term Debt | $ 1,391.6 | 1,389.2 |  |  |
Senior Notes, 3.800 Percent Due February 23, 2032 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term Debt |  |  |  | $ 395.1 |
5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Long-term Debt |  |  | $ 144.7 |  |
Senior Notes | Senior Notes, 4.35 Percent Due February 15, 2025 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated interest rate, percentage | 4.35% |  |  |  |
Long-Term Debt, Current Maturities | $ 449.9 | 0.0 |  |  |
Senior Notes | Senior Notes, 4.35 Percent Due February 15, 2025 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated interest rate, percentage | 4.35% |  |  |  |
Long-term Debt | $ 0.0 | 449.6 |  |  |
Senior Notes | Senior Notes, 2.400 Percent Due September 30, 2030 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated interest rate, percentage |  |  |  |  | 2.40%
Long-term Debt | 397.5 | 397.0 |  |  |
Senior Notes | Senior Notes, 3.800 Percent Due February 23, 2032 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated interest rate, percentage |  |  |  | 3.80% |
Long-term Debt | 396.5 | 396.0 |  |  |
Junior Debt | 5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062 |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Stated interest rate, percentage |  |  | 5.875% |  |
Long-term Debt | $ 147.7 | $ 146.6 |  |  |

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