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v3.25.4

Debt Schedule (Detail) - USD ($) $ in Millions | Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 1998
--- | --- | --- | ---
Debt Instrument |  |  |
Long-term Debt, Excluding Current Maturities | $ 3,767.6 | $ 3,465.2 |
Debt Instrument, Unamortized Discount (Premium), Noncurrent, Net | (129.2) | (131.3) |
Debt Issuance Costs, Noncurrent, Net | (36.7) | (37.0) |
Short-term debt | 0.0 | 274.6 |
Debt Instrument, Unamortized Discount, Current | 0.0 | (0.2) |
Debt Issuance Costs, Current, Net | 0.0 | 0.2 |
Long-term Debt | 3,767.6 | 3,739.8 |
Notes Issued in 1998 with 2028 Maturity Date | Senior Notes |  |  |
Debt Instrument |  |  |
Long-term Debt, Excluding Current Maturities | $ 335.8 | 335.8 |
Notes Issued in 1998 with 2028 Maturity Date | Senior Notes | Minimum |  |  |
Debt Instrument |  |  |
Stated Interest Rate of Debt | 6.75% |  |
Notes Issued in 1998 with 2028 Maturity Date | Senior Notes | Maximum |  |  |
Debt Instrument |  |  |
Stated Interest Rate of Debt | 7.25% |  |
Notes Payable due 2032 | Senior Notes |  |  |
Debt Instrument |  |  |
Long-term Debt, Excluding Current Maturities | $ 39.5 | 39.5 |
Stated Interest Rate of Debt | 7.375% |  |
Notes Payable due 2042 | Senior Notes |  |  |
Debt Instrument |  |  |
Long-term Debt, Excluding Current Maturities | $ 500.0 | 500.0 |
Stated Interest Rate of Debt | 5.75% |  |
Notes Payable due 2029 | Senior Notes |  |  |
Debt Instrument |  |  |
Long-term Debt, Excluding Current Maturities | $ 400.0 | 400.0 |
Stated Interest Rate of Debt | 4.00% |  |
Notes Payable due 2049 | Senior Notes |  |  |
Debt Instrument |  |  |
Long-term Debt, Excluding Current Maturities | $ 450.0 | 450.0 |
Stated Interest Rate of Debt | 4.50% |  |
Notes Payable due 2051 | Senior Notes |  |  |
Debt Instrument |  |  |
Long-term Debt, Excluding Current Maturities | $ 600.0 | 600.0 |
Stated Interest Rate of Debt | 4.125% |  |
Notes Payable due 2041 | Senior Notes |  |  |
Debt Instrument |  |  |
Long-term Debt, Excluding Current Maturities | $ 400.0 | 400.0 |
Stated Interest Rate of Debt | 4.046% |  |
Notes Payable due 2054 | Senior Notes |  |  |
Debt Instrument |  |  |
Long-term Debt, Excluding Current Maturities | $ 400.0 | 400.0 |
Stated Interest Rate of Debt | 6.00% |  |
Medium Term Notes Payable Due 2028 | Medium-Term Note |  |  |
Debt Instrument |  |  |
Long-term Debt, Excluding Current Maturities | $ 18.5 | 18.5 |
Stated Interest Rate of Debt | 7.19% |  |
Notes Issued in 1998 with 2038 Maturity Date | Junior Subordinated Debt |  |  |
Debt Instrument |  |  |
Long-term Debt, Excluding Current Maturities | $ 189.7 | 189.7 |
Stated Interest Rate of Debt | 7.405% |  | 7.405%
Notes Payable due 2058 | Junior Subordinated Debt |  |  |
Debt Instrument |  |  |
Long-term Debt, Excluding Current Maturities | $ 300.0 | 300.0 |
Stated Interest Rate of Debt | 6.25% |  |
Notes Payable due 2025 | Senior Notes |  |  |
Debt Instrument |  |  |
Short-term debt | $ 0.0 | 275.0 |
Stated Interest Rate of Debt | 3.875% |  |
5.250% Senior Notes due 2035 | Senior Notes |  |  |
Debt Instrument |  |  |
Stated Interest Rate of Debt | 5.25% |  |
Debt Instrument, Face Amount | $ 300.0 | $ 0.0 |

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