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Debt (Details) | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2024 USD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($) | Feb. 19, 2025 USD ($) $ / shares | Jul. 12, 2024 USD ($)
Borrowings [Abstract] |  |  |  |  |
Total long-term and current debt |  | $ 250,000,000.0 | $ 0 |  |
Long-term debt |  | 250,000,000.0 | 0 |  |
Debt Rollforward [Abstract] |  |  |  |  |
Borrowings, beginning balance |  | 0 |  |  |
Debt issued |  | 250,000,000.0 |  |  |
Debt repayments | $ 308,300,000 | 308,300,000 | 0 |  |
Borrowings, ending balance |  | 250,000,000.0 | $ 0 |  |
Borrowings, covenant, minimum interest coverage ratio | $ / shares |  |  |  | 3.0 |
Borrowings, covenant, maximum net leverage ratio | $ / shares |  |  |  | 3.5 |
Accrued interest |  | 8,200,000 |  |  |
Argonaut Transaction |  |  |  |  |
Debt Rollforward [Abstract] |  |  |  |  |
Acquired debt from Argonaut |  | 299,700,000 |  |  |
Debt repayments |  | 299,700,000 |  |  |
Revolving Credit Facility |  |  |  |  |
Borrowings [Abstract] |  |  |  |  |
Total long-term and current debt |  | 250,000,000.0 |  |  | $ 218,000,000
Debt Rollforward [Abstract] |  |  |  |  |
Borrowings, ending balance |  | 250,000,000.0 |  |  |
Undrawn borrowing facilities |  | 250,000,000 |  |  |
Borrowing facilities, maximum borrowing capacity |  | 500,000,000 |  |  |
Borrowing facilities, accordion feature |  |  |  | $ 250,000,000 |
Revolving Credit Facility | Secured Overnight Financing Rate (SOFR)1 |  |  |  |  |
Debt Rollforward [Abstract] |  |  |  |  |
Borrowings, interest rate |  |  |  | 1.45% |
Revolving Credit Facility | Carrying Amount |  |  |  |  |
Borrowings [Abstract] |  |  |  |  |
Total long-term and current debt |  | 250,000,000.0 |  |  |
Debt Rollforward [Abstract] |  |  |  |  |
Borrowings, ending balance |  | 250,000,000.0 |  |  |
Revolving Credit Facility - Drawn Amounts |  |  |  |  |
Debt Rollforward [Abstract] |  |  |  |  |
Debt issued |  | $ 250,000,000 |  |  |
Stand-by fees |  | 0.42% |  |  |
Revolving Credit Facility - Drawn Amounts | Secured Overnight Financing Rate (SOFR)1 |  |  |  |  |
Debt Rollforward [Abstract] |  |  |  |  |
Borrowings, interest rate |  | 1.875% |  |  |
Amended Revolving Credit Facility |  |  |  |  |
Debt Rollforward [Abstract] |  |  |  |  |
Borrowings, interest rate |  |  |  | 1.45% |
Stand-by fees |  | 0.29% |  |  |
Borrowing facilities, maximum borrowing capacity |  |  |  | $ 750,000,000 |
Amended Revolving Credit Facility | Secured Overnight Financing Rate (SOFR)1 |  |  |  |  |
Debt Rollforward [Abstract] |  |  |  |  |
Borrowings, interest rate |  |  |  | 2.50% |

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- Definition Borrowing Activities + References No definition available. + Details
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- Definition Borrowing Facilities, Accordion Feature, Higher Borrowing Capacity Option + References No definition available. + Details
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