Business Segments and Geographic Information - Additional Information (Detail)	3 Months Ended	9 Months Ended
Jun. 29, 2019 USD ($)	Mar. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 29, 2019 USD ($) Segment	Jun. 30, 2018 USD ($)
Segment Reporting Disclosure [Line Items]
Intangible asset and equipment impairment charges	$ 443,800,000	$ 443,800,000		$ 443,800,000	$ 46,000,000.0
Number of reportable segments \| Segment				5
Number of operating segments \| Segment				5
Revenues	$ 852,400,000		$ 824,000,000.0	$ 2,501,400,000	$ 2,404,500,000
Concentration Risk, Customer	0		0	0	0
Intersegment
Segment Reporting Disclosure [Line Items]
Revenues	$ 0		$ 0	$ 0	$ 0

Segment Reporting Disclosure [Line Items]

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Description of risks that arise due to the volume of business transacted with a particular customer. At a minimum, the description informs financial statement users of the general nature of the risk, but excludes "Information about Major Customers" that may be disclosed elsewhere (for instance, segment disclosures).

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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