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Stock Based Compensation (Details) - USD ($) |  | 12 Months Ended |
--- | --- | --- | ---
Sep. 27, 2024 | Sep. 27, 2024 | Sep. 29, 2023 | Sep. 30, 2022 | Sep. 26, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |  |  |
Vesting of stock-awards in connection with the Transaction |  | $ 13,000,000 |  |  |
Class B Units |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |  |  |
Unrecognized compensation expense | $ 0 | 0 |  |  |
Compensation expense |  | 18,000,000 | $ 3,000,000 | $ 3,000,000 |
Income tax benefits |  | $ 0 | 0 | 0 |
Time Vested Class B Units |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |  |  |
Award vesting rights, percentage |  | 20.00% |  |  |
Award vesting period |  | 5 years |  |  |
Restricted Stock Units (RSUs) |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |  |  |
Unrecognized compensation expense | $ 5,000,000 | $ 5,000,000 |  |  |
Compensation expense |  | $ 0 | $ 0 | $ 0 |
Share-based compensation, weighted average period |  | 2 years 1 month 6 days |  |  |
Restricted Stock Units (RSUs) | CMS |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |  |  |
Awards granted in the period (in shares) | 342,741 |  |  |  |
Restricted Stock Units (RSUs) | Jacobs Solutions Inc. |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |  |  |
Non-vested awards outstanding (in shares) |  |  |  |  | 65,182
Restricted Stock Units (RSUs) | Tranche One |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |  |  |
Award vesting rights, percentage |  | 50.00% |  |  |
Award vesting period |  | 2 years |  |  |
Restricted Stock Units (RSUs) | Tranche Two |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |  |  |
Award vesting rights, percentage |  | 33.00% |  |  |
Award vesting period |  | 3 years |  |  |
Restricted Stock Units (RSUs) | Tranche Three |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |  |  |
Award vesting rights, percentage |  | 25.00% |  |  |
Award vesting period |  | 4 years |  |  |
Restricted Stock Units (RSUs) | Share-Based Compensation Award, Subject To Cliff Vesting |  |  |  |  |
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] |  |  |  |  |
Award vesting period |  | 3 years |  |  |

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