Business Combinations (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 29, 2017	Sep. 30, 2016	Oct. 02, 2015
Business Acquisition [Line Items]
Payments for acquisitions, net of cash acquired	$ 13.7	$ 55.6	$ 24.6
Consideration transferred	24.8
Contingent consideration arrangements, low range of outcomes	0.0
Contingent consideration arrangements, high range of outcomes	20.0
Contingent consideration liability recorded for business combinations	10.7
Goodwill recognized through business combinations	9.7	16.6
Identifiable intangible assets	16.4
Merger termination fee	$ 0.0	$ 88.5	$ 0.0
Patents and Other [Member]
Business Acquisition [Line Items]
Useful life	5 years

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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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.

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- 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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

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For contingent consideration arrangements and indemnification assets recognized in connection with a business combination, this element represents an estimate of the low-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

+ References

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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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- Definition

Gain (loss) related to the termination of a contract between the parties. The termination may be due to many causes including early termination of a lease by a lessee, a breach of contract by one party, or a failure to perform.

+ References

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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

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- Definition

The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

+ References

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