Goodwill and Intangible Assets, Net - Reconciliation of Goodwill (Detail) - USD ($) $ in Millions	12 Months Ended
Oct. 01, 2017	Oct. 02, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Beginning balance	$ 2,479.4	$ 1,139.3
Additions from acquisitions	10.6	1,472.3
Reductions from divestitures	0.1	(125.0)
Carrying value of goodwill classified as assets held for sale	7.2	(7.2)
Ending balance	$ 2,497.3	$ 2,479.4

Goodwill, Written off (Deduction) Related to Sale of Business Unit

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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- References

No definition available.

+ Details

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- Definition

Amount of transfers into (out of) an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

+ Details

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