Goodwill and Intangibles - Schedule of Carrying Value of Goodwill by Reportable Segment Appearing in Accompanying Consolidated Balance Sheets (Details) $ in Thousands	12 Months Ended
Sep. 28, 2018 USD ($)
Goodwill [Roll Forward]
September 29, 2017	$ 3,009,826
Acquired	3,129,000
Post-Acquisition Adjustments relating to prior year acquisition	4,000
Foreign Exchange Impact	(39,000)
September 28, 2018	6,103,856
Aerospace, Technology, Environmental and Nuclear
Goodwill [Roll Forward]
September 29, 2017	1,038,000
Acquired	1,147,000
Post-Acquisition Adjustments relating to prior year acquisition	4,000
Foreign Exchange Impact	(13,000)
September 28, 2018	2,176,000
Buildings, Infrastructure and Advanced Facilities
Goodwill [Roll Forward]
September 29, 2017	1,049,000
Acquired	1,585,000
Post-Acquisition Adjustments relating to prior year acquisition	0
Foreign Exchange Impact	(14,000)
September 28, 2018	2,620,000
Energy, Chemicals and Resources
Goodwill [Roll Forward]
September 29, 2017	923,000
Acquired	397,000
Post-Acquisition Adjustments relating to prior year acquisition	0
Foreign Exchange Impact	(12,000)
September 28, 2018	$ 1,308,000

Goodwill, Adjustments During Period

No definition available.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

+ Details

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

+ Details

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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