Fair Value of Financial Instruments - Additional Information (Details) - USD ($) $ in Millions	Sep. 28, 2025	Dec. 29, 2024	Sep. 29, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Short-term investments	$ 0.0	$ 0.0	$ 489.3
Carrying cost	3,336.8	3,401.8	3,984.9
6.05% Notes Due 2034
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying cost	500.0	500.0	500.0
Fair Value, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	55.9	$ 0.6	0.6
Short-term investments			$ 489.3
Fair Value, Recurring \| US Treasury Securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale securities	$ 55.2

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity), classified as current.

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