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Discontinued Operation, Equity Method Investment Retained after Disposal, Shares Owned after Disposal

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Discontinued Operation, Receivable Balance Collected

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Discontinued Operation, Remaining Shares Held In Escrow

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Discontinued Operation, Shares Transferred to Escrow

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- Definition

Discontinued Operation, Transition Services Agreement, Expenses

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Discontinued Operation, Working Capital Adjustment

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Discontinued Operation, Working Capital Adjustment, Receivable

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- Definition

Disposal Group, Including Discontinued Operation, Fair Value Mark-to-Market, Amount

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- Definition

Shares Issued During Period, Spinoff, Conversion Ratio

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Stock Issued During Period, Shares, Spinoff Transaction

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- Definition

Amount classified as assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Amount classified as accrued liabilities attributable to disposal group held for sale or disposed of.

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Amount after tax of income (loss) from a discontinued operation attributable to the parent. 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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of income (expense) related to nonoperating activities, classified as other.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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Discontinued Operations - Narrative (Details) - USD ($) $ in Thousands								1 Months Ended		3 Months Ended		6 Months Ended
	Apr. 30, 2025	Apr. 10, 2025	Apr. 09, 2025	Mar. 28, 2025	Sep. 29, 2024	Sep. 27, 2024	Apr. 26, 2019	Mar. 28, 2025	Feb. 28, 2025	Mar. 28, 2025	Mar. 29, 2024	Mar. 28, 2025	Mar. 29, 2024
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Investment in equity securities				$ 175,859		$ 749,468		$ 175,859		$ 175,859		$ 175,859
Miscellaneous expense										(103,260)	$ (3,705)	(233,367)	$ (6,668)
Fair value mark-to-market, amount										109,500		254,700
Transition services agreement, expenses incurred										10,300		21,700
Net (Loss) Earnings Attributable to Jacobs from Discontinued Operations										(5,550)	69,876	(6,551)	113,142
Worley Stock
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Ordinary shares included in purchase price							$ 58,200
Net (Loss) Earnings Attributable to Jacobs from Discontinued Operations											(800)		(1,300)
Worley
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Consideration transferred							3,400,000
Consideration paid in cash							$ 2,800,000
Discontinued Operations, Disposed of by Means Other than Sale, Spinoff \| Subsequent Event \| Amentum Holdings, Inc.
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued operation, remaining shares held in escrow (in shares)			9,700,000
Discontinued Operations, Disposed of by Means Other than Sale, Spinoff \| SpinCo Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Stock issued during period, spinoff transaction ( in shares)						124,084,108
Shares issued during period, spinoff, conversion ratio (in shares)						1
Cash received from SpinCo business						$ 911,000
Discontinued operation, working capital adjustment								70,000
Discontinued operation, working capital adjustment, reduction in recorded receivable								24,000
Net (Loss) Earnings Attributable to Jacobs from Discontinued Operations										(5,560)	$ 70,646	(6,562)	$ 114,484
Discontinued Operations, Disposed of by Means Other than Sale, Spinoff \| SpinCo Business \| Amentum Holdings, Inc.
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Equity method investment retained, shares owned after disposal (in shares)						29,200,000
Equity method investment retained, shares transferred to escrow (in shares)						10,900,000
Discontinued operation, entitled to receive shares held in escrow (in shares)									1,200,000
Discontinued operation, remaining shares held in escrow (in shares)				9,700,000	18,300,000
Investment in equity securities				$ 175,900	$ 749,500			175,900		175,900		175,900
Disposal group, including discontinued operation, accrued liabilities				$ 44,000				$ 44,000		$ 44,000		$ 44,000
Discontinued Operations, Disposed of by Means Other than Sale, Spinoff \| SpinCo Business \| Subsequent Event
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued operation, receivable balance collected		$ 70,000
Discontinued operation, remaining shares held in escrow (in shares)	7,300,000		7,300,000
Discontinued Operations, Disposed of by Means Other than Sale, Spinoff \| SpinCo Business \| Subsequent Event \| Amentum Holdings, Inc.
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Discontinued operation, remaining shares held in escrow (in shares)			2,400,000
Miscellaneous expense			$ 21,900