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Fair value of obligations measured on a recurring basis.

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Amount of increase (decrease) of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of purchases of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Fair value portion of asset contracts related to the exchange of different currencies, including, but not limited to, foreign currency options, forward contracts, and swaps.

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Fair value as of the balance sheet date of all interest rate derivative assets designated as cash flow hedging instruments.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 815
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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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-Topic 820
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-Section 50
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Fair Value Measurements - Fair Value Assets and Liabilities Measured on Recurring Basis (Detail) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2023	Sep. 24, 2022	Sep. 25, 2021
Assets:
Assets measured at fair value on a recurring basis	$ 35.3	$ 65.3
Liabilities:
Liabilities measured at fair value on a recurring basis	2.0	23.4
Contingent consideration recorded at acquisition	1.1	0.0	$ 0.0
Fair value adjustments	(14.9)	(39.5)	$ (6.7)
Quoted Prices in Active Market for Identical Assets (Level 1)
Assets:
Assets measured at fair value on a recurring basis	0.0	0.0
Liabilities:
Liabilities measured at fair value on a recurring basis	0.0	0.0
Significant Other Observable Inputs (Level 2)
Assets:
Assets measured at fair value on a recurring basis	35.3	65.3
Liabilities:
Liabilities measured at fair value on a recurring basis	0.0	0.0
Significant Unobservable Inputs (Level 3)
Assets:
Assets measured at fair value on a recurring basis	0.0	0.0
Liabilities:
Liabilities measured at fair value on a recurring basis	2.0	23.4
Interest Rate Swap \| Quoted Prices in Active Market for Identical Assets (Level 1)
Assets:
Assets measured at fair value on a recurring basis		0.0
Liabilities:
Interest rate caps - derivative	0.0
Interest Rate Swap \| Significant Other Observable Inputs (Level 2)
Assets:
Assets measured at fair value on a recurring basis		38.9
Liabilities:
Interest rate caps - derivative	26.9
Interest Rate Swap \| Significant Unobservable Inputs (Level 3)
Assets:
Assets measured at fair value on a recurring basis		0.0
Liabilities:
Interest rate caps - derivative	0.0
Interest Rate Swap \| Assets
Assets:
Assets measured at fair value on a recurring basis		38.9
Liabilities:
Interest rate caps - derivative	26.9
Foreign Exchange Forward [Member] \| Assets
Assets:
Forward foreign currency contracts	8.4	26.4
Foreign Exchange Forward [Member] \| Assets \| Quoted Prices in Active Market for Identical Assets (Level 1)
Assets:
Forward foreign currency contracts	0.0	0.0
Foreign Exchange Forward [Member] \| Assets \| Significant Other Observable Inputs (Level 2)
Assets:
Forward foreign currency contracts	8.4	26.4
Foreign Exchange Forward [Member] \| Assets \| Significant Unobservable Inputs (Level 3)
Assets:
Forward foreign currency contracts	0.0	0.0
contingent consideration \| Liability
Liabilities:
Liabilities measured at fair value on a recurring basis	2.0	23.4
contingent consideration \| Liability \| Quoted Prices in Active Market for Identical Assets (Level 1)
Liabilities:
Liabilities measured at fair value on a recurring basis	0.0	0.0
contingent consideration \| Liability \| Significant Other Observable Inputs (Level 2)
Liabilities:
Liabilities measured at fair value on a recurring basis	0.0	0.0
contingent consideration \| Liability \| Significant Unobservable Inputs (Level 3)
Liabilities:
Liabilities measured at fair value on a recurring basis	$ 2.0	$ 23.4