XML 71 R60.htm IDEA: XBRL DOCUMENT
v3.26.1

Discontinued Operations - Narrative (Details) - USD ($) $ in Thousands |  |  |  |  |  |  | 1 Months Ended | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Apr. 30, 2025 | Apr. 10, 2025 | Apr. 07, 2025 | Mar. 13, 2025 | Sep. 27, 2024 | Apr. 26, 2019 | Mar. 31, 2025 | Feb. 28, 2025 | Jun. 26, 2026 | Jun. 27, 2025 | Mar. 28, 2025 | Jun. 26, 2026 | Jun. 27, 2025 | Sep. 26, 2025
Disposal Group, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Investment in equity securities |  |  |  |  |  |  |  |  | $ 6,198 |  |  | $ 6,198 |  | $ 0
Miscellaneous income (expense), net |  |  |  |  |  |  |  |  | 890 | $ 38,844 |  | (16,480) | $ (194,523) |
(Gain) loss on investment in equity securities |  |  |  |  |  |  |  |  |  | (27,400) |  | (6,198) | 227,305 |
Transition services agreement, expenses incurred |  |  |  |  |  |  |  |  | $ 0 | (9,800) |  | 0 | (31,500) |
Worley Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disposal Group, Including Discontinued Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Business combination consideration equity issued |  |  |  |  |  | $ 58,200 |  |  |  |  |  |  |  |
Worley |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disposal Group, 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 | Amentum Holdings, Inc. |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disposal Group, 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 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disposal Group, 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 |  |  |  |  |  |  |
Discontinued operation, receivable balance collected |  | $ 70,000 |  |  |  |  |  |  |  |  |  |  |  |
Discontinued net cash flows from operating activities |  |  |  |  |  |  |  |  |  | $ (2,400) |  | $ (32,700) | $ (2,400) |
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 | Amentum Holdings, Inc. |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disposal Group, 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, remaining shares held in escrow (in shares) |  |  | 2,400,000 | 9,700,000 | 18,300,000 |  |  |  |  |  |  |  |  |
Investment in equity securities |  |  |  |  | $ 749,500 |  |  |  |  |  |  |  |  |
Discontinued operation, entitled to receive shares held in escrow (in shares) |  |  |  |  |  |  |  | 1,200,000 |  |  |  |  |  |
Miscellaneous income (expense), net |  |  |  |  |  |  |  |  |  |  | $ 21,900 |  |  |

X
- Definition Discontinued Operation, Entitled to Receive Shares Held In Escrow + References No definition available. + Details
Name: | jec_DiscontinuedOperationEntitledToReceiveSharesHeldInEscrow
Namespace Prefix: | jec_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Discontinued Operation, Equity Method Investment Retained after Disposal, Shares Owned after Disposal + References No definition available. + Details
Name: | jec_DiscontinuedOperationEquityMethodInvestmentRetainedAfterDisposalSharesOwnedAfterDisposal
Namespace Prefix: | jec_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Discontinued Operation, Receivable Balance Collected + References No definition available. + Details
Name: | jec_DiscontinuedOperationReceivableBalanceCollected
Namespace Prefix: | jec_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Discontinued Operation, Remaining Shares Held In Escrow + References No definition available. + Details
Name: | jec_DiscontinuedOperationRemainingSharesHeldInEscrow
Namespace Prefix: | jec_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Discontinued Operation, Shares Transferred to Escrow + References No definition available. + Details
Name: | jec_DiscontinuedOperationSharesTransferredToEscrow
Namespace Prefix: | jec_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Discontinued Operation, Transition Services Agreement, Expenses (Income) + References No definition available. + Details
Name: | jec_DiscontinuedOperationTransitionServicesAgreementExpensesIncome
Namespace Prefix: | jec_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Discontinued Operation, Working Capital Adjustment + References No definition available. + Details
Name: | jec_DiscontinuedOperationWorkingCapitalAdjustment
Namespace Prefix: | jec_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Discontinued Operation, Working Capital Adjustment, Receivable + References No definition available. + Details
Name: | jec_DiscontinuedOperationWorkingCapitalAdjustmentReceivable
Namespace Prefix: | jec_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Shares Issued During Period, Spinoff, Conversion Ratio + References No definition available. + Details
Name: | jec_SharesIssuedDuringPeriodSpinoffConversionRatio
Namespace Prefix: | jec_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Stock Issued During Period, Shares, Spinoff Transaction + References No definition available. + Details
Name: | jec_StockIssuedDuringPeriodSharesSpinoffTransaction
Namespace Prefix: | jec_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482099/360-10-50-3 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 14 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482130/360-10-45-14 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5C -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-5C Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5B -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-5B Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483475/205-20-45-11 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483475/205-20-45-10 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5C -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-5C + Details
Name: | us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 805 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 41 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479303/805-10-55-41 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 805 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479328/805-10-50-8 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 805 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479581/805-30-50-2 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 805 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479581/805-30-50-1 + Details
Name: | us-gaap_BusinessCombinationConsiderationTransferred1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 805 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 41 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479303/805-10-55-41 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 805 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479328/805-10-50-8 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 805 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479581/805-30-50-2 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 805 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(4) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479581/805-30-50-1 Reference 5: http://www.xbrl.org/2003/role/exampleRef -Topic 805 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 42 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479303/805-10-55-42 + Details
Name: | us-gaap_BusinessCombinationConsiderationTransferredEquityInterestsIssuedAndIssuable
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of unrealized and realized gain (loss) on investment in debt and equity securities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(9)(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(7)(c)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2 + Details
Name: | us-gaap_DebtAndEquitySecuritiesGainLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount before tax of income (loss) from operations classified as a discontinued operation. Excludes gain (loss) on disposal and provision for gain (loss) until its disposal. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 103 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483474/205-20-55-103 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5C -Subparagraph (b)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-5C Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483475/205-20-45-3 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5C -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-5C Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5B -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-5B + Details
Name: | us-gaap_DiscontinuedOperationIncomeLossFromDiscontinuedOperationDuringPhaseOutPeriodBeforeIncomeTax
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482099/360-10-50-3 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 14 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482130/360-10-45-14 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3A -Subparagraph (b)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482099/360-10-50-3A Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3A -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482099/360-10-50-3A Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3A -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482099/360-10-50-3A Reference 6: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3A -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482099/360-10-50-3A Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482099/360-10-50-3 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482099/360-10-50-3 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482099/360-10-50-3 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482099/360-10-50-3 Reference 11: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 5 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482130/360-10-45-5 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Topic 360 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482099/360-10-50-3 Reference 13: http://www.xbrl.org/2003/role/exampleRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 102 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483474/205-20-55-102 Reference 14: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483475/205-20-45-10 Reference 15: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4B -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-4B Reference 16: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.Z.5.Q2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480781/205-20-S99-2 Reference 17: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section S45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480868/205-20-S45-2 Reference 18: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4B -Subparagraph (d)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-4B Reference 19: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4B -Subparagraph (d)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-4B Reference 20: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5C -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-5C Reference 21: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4B -Subparagraph (c)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-4B Reference 22: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4B -Subparagraph (d)(4) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-4B Reference 23: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4B -Subparagraph (d)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-4B Reference 24: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4B -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-4B Reference 25: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-1 Reference 26: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5C -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-5C Reference 27: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5B -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-5B Reference 28: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483475/205-20-45-11 Reference 29: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section S99 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480781/205-20-S99-3 Reference 30: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section S50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480837/205-20-S50-1 Reference 31: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5B -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-5B Reference 32: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5C -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-5C Reference 33: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-3 Reference 34: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-1 Reference 35: http://www.xbrl.org/2003/role/disclosureRef -Topic 205 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483499/205-20-50-1 + Details
Name: | us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of income (expense) related to nonoperating activities, classified as other. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4A -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4A Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(9)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2 + Details
Name: | us-gaap_OtherNonoperatingIncomeExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 805 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 41 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479303/805-10-55-41 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 805 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479328/805-10-50-8 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 805 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479581/805-30-50-2 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 805 -SubTopic 30 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479581/805-30-50-1 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-13 + Details
Name: | us-gaap_PaymentsToAcquireBusinessesGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-12 + Details
Name: | us-gaap_ProceedsFromDivestitureOfBusinesses
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=jec_WorleyStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=jec_WorleyParsonsLimitedECRBusinessMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DisposalGroupClassificationAxis=us-gaap_DiscontinuedOperationsDisposedOfByMeansOtherThanSaleSpinoffMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=jec_AmentumHoldingsInc.Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_IncomeStatementBalanceSheetAndAdditionalDisclosuresByDisposalGroupsIncludingDiscontinuedOperationsAxis=jec_SpinCoBusinessMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |