Goodwill and Intangibles (Schedule of Carrying Value of Goodwill by Reportable Segment Appearing in Accompanying Consolidated Balance Sheets) (Details) $ in Thousands	3 Months Ended
Dec. 29, 2017 USD ($)
Goodwill [Line Items]
Balance September 29, 2017	$ 3,009,826
Acquired	2,698,800
Foreign Exchange Impact	12,300
Balance December 29, 2017	5,720,875
Aerospace & Technology
Goodwill [Line Items]
Balance September 29, 2017	1,025,800
Acquired	945,200
Foreign Exchange Impact	4,200
Balance December 29, 2017	1,975,200
Buildings & Infrastructure
Goodwill [Line Items]
Balance September 29, 2017	751,400
Acquired	1,417,900
Foreign Exchange Impact	3,100
Balance December 29, 2017	2,172,400
Industrial
Goodwill [Line Items]
Balance September 29, 2017	561,800
Foreign Exchange Impact	2,300
Balance December 29, 2017	564,100
Petroleum & Chemicals
Goodwill [Line Items]
Balance September 29, 2017	670,800
Acquired	335,700
Foreign Exchange Impact	2,700
Balance December 29, 2017	$ 1,009,200

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.

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

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