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v3.25.3

Debt - Narrative (Details) |  |  |  | 3 Months Ended | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Jan. 15, 2025 USD ($) | Mar. 15, 2022 USD ($) | Mar. 10, 2022 USD ($) deferral_period | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Dec. 31, 2024 USD ($) | Mar. 16, 2022 USD ($) | Feb. 15, 2022 USD ($)
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  | $ 943,100,000 |  | $ 943,100,000 |  | $ 1,391,600,000 |  |
Interest and other expenses |  |  |  | 9,100,000 | $ 14,400,000 | 29,500,000 | $ 42,300,000 |  |  |
Interest paid, including capitalized interest, operating and investing activities |  |  |  | $ 14,800,000 | $ 24,700,000 | $ 41,900,000 | $ 52,000,000.0 |  |  |
Senior Notes | Senior Notes, 4.35 Percent Due February 15, 2025 |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Stated interest rate |  |  |  | 4.35% |  | 4.35% |  |  |  |
Long-term debt, gross | $ 450,000,000.0 |  |  |  |  |  |  |  |  |
Redemption price, percentage | 100.00% |  |  |  |  |  |  |  |  |
Senior Notes | Senior Notes, 2.400 Percent Due September 30, 2030 |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Stated interest rate |  |  |  | 2.40% |  | 2.40% |  |  |  |
Long-term debt, gross |  |  |  | $ 400,000,000.0 |  | $ 400,000,000.0 |  |  |  |
Face amount of debt |  |  |  | $ 395,800,000 |  | $ 395,800,000 |  |  |  |
Effective interest rate |  |  |  | 2.52% |  | 2.52% |  |  |  |
Long-term debt |  |  |  | $ 397,800,000 |  | $ 397,800,000 |  | 397,500,000 |  |
Senior Notes | Senior Notes, 3.800 Percent Due February 23, 2033 |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Stated interest rate |  |  |  | 3.80% |  | 3.80% |  |  |  |
Long-term debt, gross |  |  |  |  |  |  |  |  |  | $ 400,000,000
Effective interest rate |  |  |  | 3.95% |  | 3.95% |  |  |  |
Long-term debt |  |  |  | $ 396,800,000 |  | $ 396,800,000 |  | 396,500,000 |  | $ 395,100,000
Junior Debt | 5.875% Fixed-Rate Reset Junior Subordinated Debentures due 2062 |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Stated interest rate |  |  |  | 5.875% |  | 5.875% |  |  |  |
Long-term debt, gross |  |  | $ 150,000,000 |  |  |  |  |  |  |
Long-term debt |  |  | $ 144,700,000 | $ 148,500,000 |  | $ 148,500,000 |  | 147,700,000 |  |
Debt instrument, basis spread on variable rate |  |  | 4.14% |  |  |  |  |  |  |
Debt instrument, interest deferrals, number of deferral periods | deferral_period |  |  | 1 |  |  |  |  |  |  |
Debt instrument, interest deferrals, period |  |  | 5 years |  |  |  |  |  |  |
Revolving Credit Facility | Notes Payable under Revolving Credit Agreement | Second Amended and Restated Credit Agreement |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |
Line of credit facility, maximum borrowing capacity |  | $ 600,000,000.0 |  |  |  |  |  |  | $ 800,000,000.0 |
Increase in revolving credit borrowing capacity |  | $ 200,000,000.0 |  |  |  |  |  |  |  |
Line of credit facility, amount outstanding |  |  |  | $ 0 |  | $ 0 |  | $ 0 |  |

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