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Retirement Benefit Plan - Additional Information (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024 | Dec. 31, 2024
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items] |  |  |  |  |
Shares fully vested, Description |  |  | Shares allocated to a participant’s account are fully vested after three years of credited service, or in the event(s) of reaching age 65, death or disability while an active employee of the Company. |  |
Shares fully vested after credited service |  |  | 3 years |  |
Common stock shares outstanding including ESOP | 106,488,033 |  | 106,488,033 |  | 106,775,350
Company's stock held by ESOP | 50,952,945 |  | 50,952,945 |  | 54,117,904
Direct Costs of Contracts and Selling, General and Administrative Expense |  |  |  |  |
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items] |  |  |  |  |
ESOP contribution expense | $ 18.6 | $ 13.2 | $ 54.0 | $ 43.4 |

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