Defined Benefit Plan, Increase (Decrease) Due To Pension Ruling

No definition available.

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- 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

No definition available.

+ Details

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- Definition

Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

+ References

+ Details

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- Definition

Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (h)(1)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

+ Details

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- Details

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- Details

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- Details

Name:	us-gaap_PlanNameAxis=jec_SverdrupPensionPlanMember
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Pension and Other Postretirement Benefit Plans - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended			6 Months Ended
	Dec. 31, 2017	Mar. 29, 2019	Dec. 28, 2018	Mar. 30, 2018	Mar. 29, 2019	Mar. 30, 2018
Defined Benefit Plan Disclosure [Line Items]
Service cost		$ 2,127		$ 2,696	$ 4,333	$ 4,977
Plan Amendment and settlement gain		32,449		0	34,621	(3,819)
Increase due to pension ruling			$ 38,200		800
Accounting Standards Update 2017-07 \| Miscellaneous Income (Expense), Net
Defined Benefit Plan Disclosure [Line Items]
Service cost		$ 6,100		$ 6,000	$ 12,200	$ 12,100
CH2M Hill and OMI Retiree Medical Plans
Defined Benefit Plan Disclosure [Line Items]
Plan Amendment and settlement gain			$ 2,200
Sverdrup Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Plan Amendment and settlement gain	$ (3,800)