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Legal Proceedings and Commitments and Contingencies (Details) - USD ($) $ in Millions | 1 Months Ended |  |
--- | --- | --- | ---
Jan. 31, 2020 | Sep. 27, 2024 | Sep. 29, 2023
Loss Contingencies [Line Items] |  |  |
Estimate of possible loss |  | $ 138 | $ 138
Other long-term liabilities |  | $ 125 | $ 125
AECOM Energy & Construction Inc. |  |  |
Loss Contingencies [Line Items] |  |  |
Percentage of claim recovery and costs assumed | 10.00% |  |
Percentage of claim recovery and costs retained by seller | 90.00% |  |

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