v3.25.4

Discontinued Operations- Schedule of Earnings (Loss) From Discontinued Operations, Net of tax (Details) - USD ($) $ in Thousands	3 Months Ended
	Dec. 26, 2025	Dec. 27, 2024
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
Net (Loss) Earnings of the Group from Discontinued Operations	$ 554	$ (1,001)
Net Earnings (Loss) Attributable to Jacobs from Discontinued Operations	554	(1,001)
Discontinued Operations, Disposed of by Means Other than Sale, Spinoff \| SpinCo Business
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
Revenues	0	64
Direct cost of contracts	0	(60)
Gross (loss) profit	0	4
Selling, general and administrative expense	487	(1,348)
Operating (Loss) Profit	487	(1,344)
Other income, net	0	0
(Loss) Earnings Before Taxes from Discontinued Operations	487	(1,344)
Income Tax Benefit (Expense)	67	343
Net (Loss) Earnings of the Group from Discontinued Operations	554	(1,001)
Net Earnings Attributable to Noncontrolling Interests from Discontinued Operations	0	0
Net Earnings (Loss) Attributable to Jacobs from Discontinued Operations	554	$ (1,001)
Disposal group, including discontinued operation, foreign tax indemnity reserve release	$ 800

Disposal Group, Including Discontinued Operation, Costs of Goods Sold, Net of Expense Reversal

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Disposal Group, Including Discontinued Operation, Foreign Tax Indemnity Reserve Release

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Disposal Group, Including Discontinued Operation, Other Income, Net of Expenses

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Amount before tax of income (loss) from a discontinued operation. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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Amount of tax expense (benefit) related to a discontinued operation. Includes, but is not limited to, tax expense (benefit) related to income (loss) from operations during the phase-out period, tax expense (benefit) related to gain (loss) on disposal, tax expense (benefit) related to gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and tax expense (benefit) related to adjustments of a prior period gain (loss) on disposal.

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Amount of gross profit attributable to disposal group, including, but not limited to, discontinued operation.

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Amount of operating income (loss) attributable to disposal group, including, but not limited to, discontinued operation.

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Amount after tax of income (loss) from a discontinued operation including the portion attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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Amount after tax of income (loss) from a discontinued operation attributable to the noncontrolling interest. Includes, but is not limited to, the income (loss) from operations during the phase-out period, gain (loss) on disposal, gain (loss) for reversal of write-down (write-down) to fair value, less cost to sell, and adjustments to a prior period gain (loss) on disposal.

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JACOBS SOLUTIONS INC. 10-Q