Income Taxes - Activity of Company's Unrecognized Income Tax Benefits (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 27, 2025	Sep. 28, 2024	Sep. 30, 2023
Income Tax Disclosure [Abstract]
Balance at beginning of fiscal year	$ 273.2	$ 256.5	$ 247.6
Tax positions related to current year:
Additions	6.7	7.8	6.8
Tax positions related to prior years:
Additions related to change in estimate	10.5	11.8	4.5
Reductions	(0.6)	(2.1)	0.0
Lapses in statutes of limitations and settlements	(25.3)	(0.8)	(2.4)
Additions related to reserves acquired from acquisitions	1.9	0.0	0.0
Balance as of the end of the fiscal year	$ 266.4	$ 273.2	$ 256.5

Tax positions related to current year.

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Tax positions related to prior years.

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Amount of unrecognized tax benefits.

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Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 217
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482663/740-10-55-217

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of increase in unrecognized tax benefits resulting from acquisitions.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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