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Stock Based Compensation (Details) - USD ($)		12 Months Ended
Stock Based Compensation (Details) - USD ($)	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